2015 Air Force Academy Weed Management Plan.pdf

Integrated Noxious

Weed Management

Plan

August 2015

US Air Force Academy and Farish Recreation

Area

CNHP’s mission is to preserve the natural diversity of life by contributing the essential scientific foundation that leads to lasting conservation of Colorado's biological wealth.

Colorado Natural Heritage Program Warner College of Natural Resources

Colorado State University 1475 Campus Delivery Fort Collins, CO 80523

(970) 491-7331

Report Prepared for:

United States Air Force Academy Department of Natural Resources

Recommended Citation:

Smith, P., S. S. Panjabi, and J. Handwerk. 2015. Integrated Noxious Weed Management Plan: US Air Force

Academy and Farish Recreation Area, El Paso County, CO. Colorado Natural Heritage Program, Colorado State

University, Fort Collins, Colorado.

Front Cover: Documenting weeds at the US Air Force Academy.

Photos courtesy of the Colorado Natural Heritage Program ©

Integrated Noxious Weed Management Plan

US Air Force Academy and

Farish Recreation Area

El Paso County, CO

Pam Smith, Susan Spackman Panjabi, and Jill Handwerk Colorado Natural Heritage Program

Warner College of Natural Resources

Colorado State University

Fort Collins, Colorado 80523

August 2015

Air Force Academy Integrated Noxious Weed Management Plan i

EXECUTIVE SUMMARY

Various federal, state, and local laws, ordinances, orders, and policies require land managers to control noxious weeds. The purpose of this plan is to provide a guide to manage, in the most efficient and effective manner, the noxious weeds on the US Air Force Academy (Academy) and Farish Recreation Area (Farish) over the next 10 years (through 2025), in accordance with their respective integrated natural resources management plans. This plan pertains to the

“natural” portions of the Academy and excludes highly developed areas, such as around buildings, recreation fields, and lawns. This plan covers the entire Farish site, including the developed areas.

For clarification purposes, throughout this report, the word “we” refers to the authors of this report, Colorado Natural Heritage Program (Smith et al. 2015).

An integrated weed management plan employs a combination of weed control strategies in an effort to protect and/or achieve lasting restoration of native plant communities and the natural processes that support them. This plan follows approaches utilized by Carpenter and Perce (2004) who wrote the previous management plan as well as various other management plans that are designed for weed management in areas that contain natural resources that need protection

(Person and Ortega 2009, Spackman Panjabi and Decker 2007, Tu et al. 2001 and Randal 2001). In addition, new information on weed control methods was gleaned from contemporary scientific literature, a Colorado State University Extension Course (Exploring Herbicide Use in Natural Areas, G. Beck 2015), CSU Extension Fact Sheets, and management recommendations from El Paso County

(2014) and the US Forest Service Fire Effects Information Service (FEIS 2015) which have been incorporated into this plan.

A key element of a management plan is to compile a complete list and map of the noxious weeds known from the management area. A noxious weed survey of the Academy and Farish was conducted by the Colorado Natural Heritage Program during 2002, 2007, and 2012 with a subset of species mapped on an annual basis (Anderson et al. 2003, Anderson and Lavender 2006, 2007, 2008, Anderson, Lavender and Neid 2009, Anderson et al. 2010, Rondeau et al 2011, 2014, Rondeau and Lavender 2012, 2013). These studies documented 8,308 locations of at least 25 (Colorado

State List A,B,C) noxious weed species. While many of these infestations have been treated over the years and the noxious weed targets have changed, all mapped weed locations were used in the development of this strategy, given the assumption that treated infestations have the potential to re-surface over time. Such a large number of weed locations necessitated a prioritization process to reduce the number of occurrences to be controlled to a manageable number. The noxious weed species were prioritized for control based on three factors: 1) the extent of the infestation;

2) the feasibility of successful control and 3) the proximity to areas with natural values (i.e.

proximity to a rare plant or animal habitat or location within a rare plant community). To assist in determining whether a location was in a natural area or an area with natural value(s) we have designated areas referred to as Special Weed Management Areas (SWMAs). This results in a total of approximately 6,189 noxious weed occurrences for which we recommend a “natural areas” management approach, which is about 74% of the total number of mapped occurrences. Currently, 4,654 of the 6,189 occurrences are extant (pers. comm. A. Greenwell 2015).

ii Colorado Natural Heritage Program © 2015

Weed management objectives have been established for the 20 most significant weed species at the

Academy within designated SWMAs. Six species (myrtle spurge, bouncingbet, Dalmatian toadflax, dame’s rocket, Russian knapweed, and salt cedar) are slated for eradication. Three species previously considered candidates for eradication across the Academy, houndstongue, Scotch thistle and St. Johnswort, are slated for eradication and/or control because these species have reached coverage approaching or exceeding one acre and are widespread in distribution at the Academy and eradication may no longer be a realistic goal. All other species are slated for suppression or containment. However, in some cases, any one of the 20 weed species may need to be slated for elimination at a local level, especially at the intersection with important natural resources

(SWMAs).

There are five viable broad categories of weed management techniques that could be employed at the Academy and Farish. These include prevention, manual, biological, chemical, and prescribed burning. A most effective/lasting approach will integrate a combination of several techniques. An integrated weed management plan that includes revegetation with native plants, and selects multiple control techniques that ideally interact to provide effective and feasible control for each target weed species will result in the most successful restoration results. More detailed restoration plans are needed for treating infestations in some locations of the Special Weed Management Areas, particularly areas that support habitat for the Listed Threatened Preble’s meadow jumping mouse and other biological elements of concern that are mapped at the Academy. To that end we have recommended specific weed management techniques for each of the 20 target weed species known on the Academy and Farish and have provided digital polygons for the locations of the natural resources and Special Weed Management Areas that can be used by contractors and Academy staff.

Prevention measures are by far the most effective tool for weed control; it is essential to minimize the entry of new noxious weed species to the Academy and Farish, as well as to locate and eliminate new, small occurrences before they can become established. Several policies and actions that we believe will greatly reduce the entry of new weeds to the Academy and Farish and reduce the likelihood of inadvertently spreading weeds within these properties are utilized by the Academy.

These include requiring heavy equipment used for construction, forest management, and firefighting to be cleaned before entering the Academy or moving between construction sites within the Academy; working with the base stables to improve the condition of ranges where the government-owned horses graze; prohibiting noxious weeds and certain other invasive plants species from being planted at the Academy and Farish; and promptly revegetating with native plant species all disturbances created by construction, logging, and firefighting. Further, periodic weed surveys are also recommended for early detection and rapid response of new infestations.

The success of any treatment program needs to be evaluated. We have proposed the continuation of a monitoring program to evaluate the effectiveness of weed management actions. Broadly speaking, monitoring will follow Rondeau and Greenwell (2014), and involve collecting photographs and vegetation data in permanent plots in selected weed occurrences that are being actively managed. It is also important to properly interpret results and to record actions taken by the Academy (location of type of treatments each year).

Air Force Academy Integrated Noxious Weed Management Plan iii

The Air Force Academy supports at least 31 different elements of conservation concern, including a

Federally Listed Threatened species (Preble’s meadow jumping mouse). We also recommend monitoring the elements of conservation concern which include rare plants, animals, and high quality plant communities (CNHP 2015), to ensure these areas do not become degraded by noxious weeds. In general, weed control efforts, albeit well meaning, can be detrimental to these natural resources, and should be approached with consideration for the long term viability of the communities and local processes that support these natural values. In areas that support rare species and/or high quality plant communities, a “natural area” approach is recommended for all weed management activities/efforts.

A list of actions that can be undertaken immediately to begin to implement this plan include:

1) Continue to monitor and map 20 target noxious weed species using established protocols

(Lavender et al. 2015).

2) Continue successful Rapid Response Early Detection (RRED) efforts for Russian knapweed, Dalmatian toadflax, myrtle spurge and salt cedar.

3) Utilize and monitor biocontrol agents present at the Academy.

4) Utilize a “natural areas” approach for noxious weeds located in the mapped Special Weed

Management Areas.

5) Conduct follow-up monitoring on treated areas and evaluate success.

6) Maintain records on treatments and treatment areas, and make them available to field workers and for data analysis.

7) Reduce herbicide use by using manual methods when appropriate.

8) Protect wetlands and groundwater by avoiding herbicide use in drainages, lakeshores, riparian areas and floodplains.

9) Monitor rare species and plant communities in proximity to noxious weed species.

10) Review the literature for current updates on successful weed treatments. Incorporate new scientific information and results from monitoring data into treatment strategies.

11) Provide a yearly workshop or annual meeting with the Academy staff, Colorado Natural

Heritage Program and weed contractors to share observations and ideas.

12) Look for natural biological controls that may be present on Canada thistle and Russian olive.

13) Be aware of, and know how to identify List A species that have the potential spread to landscapes at the Academy.

iv Colorado Natural Heritage Program © 2015

ACKNOWLEDGEMENTS

The authors would like to acknowledge Dr. Brian Mihlbachler, Natural Resource Manager and Fish and Wildlife Biologist with the U.S. Fish & Wildlife Service, who is stationed at the Academy and has been instrumental in guiding weed management activates at the Academy and Farish over the past

15 years. Renee Rondeau and Amy Greenwell provided important data on weed locations and monitoring results, and well as guidance regarding the conceptual approaches used in this strategy.

Alan Carpenter and Steven Perce’s work on the 2004 plan gave us a great start and framework for this updated strategy.

Air Force Academy Integrated Noxious Weed Management Plan v

TABLE OF CONTENTS

Executive Summary .................................................................................................................................................................. i

Acknowledgements ............................................................................................................................................................... iv

1.0 Introduction

1.1 Purpose and Need

1.2 Management Area

Climate

Physiography and Geology

Soils

Surface water, wetlands, drainages and riparian areas

Plant Communities

Wildlife

Rare Plants, Animals, and Significant Plant Communities

Conservation Areas

1.3 Noxious Weed Legislation

Sikes Act

Federal Noxious Weed Act

Executive Order 13112

U.S. Air Force Regulatory Requirements

Colorado Noxious Weed Act

El Paso County Weed Management Program

1.4 Past and on-going weed management at the U.S. Air Force Academy

Biocontrol

Herbicides

Mechanical Removal

2.0 Target Weed Species 2015

2.1 Priorities for Weed Management

Priority Species

Weed Management Objectives

2.2 Special Weed Management Areas (SWMAs)

2.3 Weed Management in Natural Areas

vi Colorado Natural Heritage Program © 2015

3.0 Integrated Weed Management

3.1 Preventative

3.2 Cultural

3.3 Mechanical

Hand Pulling

Mowing and Cutting

Prescribed Burning

3.4 Biological Control

Brown-legged leafy spurge flea beetle

3.5 Chemical

Accurate Plant Identification

Timing

Persistence

Toxicity to non-target plants and animals

Sprayer Calibration

Pesticide Resistance

Biocontrol agents

Adjuvants

Safety for Field Personnel/Exposure

Recommendations for Record Keeping and Evaluation

4.0 Species Specific Weed Management Recommendations

Detailed Species Specific Recommendations

LIST A

LIST B

LIST C

INVASIVE PLANTED SPECIES NOT ON STATE WEED LIST

5.0 Follow-up Monitoring and Evaluation

Adjusting Weed Management Actions

Future/On-going Weed Survey Needs

SUMMARY OF RECOMMENDATIONS

6.0 References

Air Force Academy Integrated Noxious Weed Management Plan vii

TABLE OF FIGURES

Figure 1: Location of the Air Force Academy and Farish Recreation Area in El Paso County, Colorado………………………………………………………………………………………………………………………………..2

Figure 2. Summary data for annual precipitation…………………………………………………………………….3

Figure 3: Monument Creek and Named Tributaries…………………………………………………………………5

Figure 4. Potential Conservation Area (PCA) at Farish Recreation Area…………………………………….9

Figure 5. Location of Four Potential Conservation Areas (PCAs) and New Element Occurrences (EORs) at the Air Force Academy in 2015………………………………………………………………………………10

Figure 6. Special Weed Management Area at the U.S. Air Force Academy………………………………...21

TABLE OF TABLES

Table 1. Rare animals, significant plant communities, and rare plants documented at the Air Force

Academy and Farish Recreation Area………………………………………………………………………………………..7

Table 2. Biodiversity Ranks and Definitions……………………………………………………………………………

Table 3. List of Potential Conservation Areas at the Academy and Farish……………………………….…….9

Table 4. List A, B, C and Watch List Definitions…………………………………………………………………………13

Table 5. List of Noxious Weeds documented at the Academy and Farish as of 2014…………………….16

Table 6. Factors that influence priorities for management for noxious weed species at the Air Force Academy and the Farish Recreation Area…………………………………………………………………………………..20

Table 7. List of Biocontrol Agents that have been released or documented at the U.S. Air Force

Academy 2000-2014 (Michels et al. 2001, 2011, 2014)………………………………………………………………26

Table 8. Approximate level of infestation, life form, and recommendations for treatment of 20 target weed species at the Academy and Farish that are located within Special Weed Management Areas (SWMAs)…………………………………………………………………………………………………………………..……..41

Table 9. Recommended monitoring of targeted noxious weed species at the Air Force Academy or

Farish Recreation Area………………………………………………………………………………………………………………44

Air Force Academy Integrated Noxious Weed Management Plan 1

1.0 INTRODUCTION

Weed management plans are intended to help weed managers make the best use of available time and funding by determining which invasive species, and which specific infestations of those species should be the primary focus of weed control and restoration efforts. Based on weed mapping and monitoring efforts that have been conducted at the Academy between 2001- 2015, it is clear that managing all noxious weeds found on the property is not possible. This is typical of almost all landscapes in developed areas along the Front Range of Colorado. An Integrated Noxious Weed

Plan for the Academy was completed in 2004 (Carpenter and Perce 2004) to establish a plan to prioritize weed species for control; this report provides an update to that plan.

A number of critical biological resources including rare plants, animals and plant communities have been identified at the Academy and Farish over the years (CNHP 2012). Weed management plans for areas that harbor critical biological elements need to assess the potential harm from weeds and as well as potential harm from weed treatments. It is much more complicated to manage weeds in a natural system than it is to manage weeds in an agricultural setting. A complex system of wetlands and drainages also occur at the Academy which pose additional challenges for successful weed management. Weed management in natural areas concepts are incorporated into this management plan by not only identifying and prioritizing weed species for control but by also delineating areas with significant natural resources. Consideration of the impacts of removal of target weed species should be evaluated by weighing potential harm and/or gains for each site, particularly those with significant natural features.

1.1 Purpose and Need

The purpose of this integrated noxious weed management plan is to provide a guide to manage, in the most efficient and effective manner, the noxious weeds on the Air Force Academy and the

Farish Recreation Area over the next 10 years (through 2025) in accordance with their respective integrated natural resources management plans. A periodically updated Integrated Noxious Weed

Management Plan that includes a monitoring component for pre- and post-treatment efforts is the most effective tool for managing weed populations. Since the previous management plan was written, more information has become available from the ongoing studies at the Academy, as well as new scientific data. This new information has been used to update the existing management plan to target management needs for weed infestations that are a priority for control efforts at the

Academy and Farish.

1.2 Management Area

The Academy is located in Colorado Springs, El Paso County, Colorado (Figure 1) and includes

18,445 acres of land. The Farish Recreation Area includes 655 acres of forest and grassland, as well as three man-made lakes. Extensive areas at the Academy include lands with dense vegetation.

Therefore, it is important to note that locating all of the noxious weeds, despite frequent weed

2 Colorado Natural Heritage Program © 2015 mapping efforts, is likely not possible. New species and occurrences have been, and will continue to be found at the Academy. This is one of the primary reasons for revising weed management plans.

The 2015 Weed Management plan pertains to the “natural” portions of the Air Force Academy and excludes highly developed areas, such as around buildings, recreation fields, and lawns. In addition, this plan covers the entire Farish Recreation Area site, including the limited developed areas.

Figure 1. Location of the Air Force Academy and Farish Recreation Area in El Paso County, Colorado.

Air Force Academy Integrated Noxious Weed Management Plan 3

Climate

Climate is important in understanding many aspects of plant growth and is considered in weed population trends and in the interpretation of monitoring results.

The Academy is located in a semi-arid area. The local weather station received an average annual precipitation of 15.4 inches from 1979 – 1991 (ESCO Associates, Inc. 1992) and 16.4 inches from

1992 – 2003 (unpublished data from USAFA airfield). Wetlands and riparian areas are often much wetter than the average annual precipitation would indicate because they receive supplemental moisture from storm water and effluent discharges, surface flow and/or groundwater. However, precipitation in the greater Colorado Springs area has been below normal 11 of the past 15 years

(Figure 2).

Figure 2. Summary data for annual precipitation by water year (October-September) at Colorado Springs, Colorado from 2002 through 2014 (Western Regional Climate Center 2014). Average annual precipitation (1961-1990) is 16.3 inches. Spring = March-May, Summer = June-August

-90%

-70%

-50%

-30%

-10%

10%

30%

50%

70%

90%

-2

-2

-2

-2

-2

-2

-2

-2

-2

-2

-2

-2

-2

D ep ar tu re f ro m n o rm al

Water year (Oct-Sep)

Precipitation at Station 51778 COSprings WSO AP Spring =Mar-May, summer = Jun-Aug

Annual precipitation Summer precipitation Spring precipitaion

4 Colorado Natural Heritage Program © 2015

Physiography and Geology

The primary physical feature of the Academy is a series of east-west trending ridges that are comprised of arkosic sandstones (Ripley 1994). The ridges create south- and north-facing slopes.

Generally, the south-facing slopes are relatively hot and dry, while the north-facing slopes are cooler and moister. These north-facing slope environments are preferred by different species of noxious weeds. The elevation of the Academy ranges from 6,376 feet along Monument Creek to

7,899 feet at Stanley Canyon.

The Farish Recreation Area is located west of the Academy in the Rampart Range, which consists mostly of Pikes Peak granite. The elevation of Farish ranges from 9,048 feet along Beaver Creek to

9,315 feet south of Schubarth Road.

Soils

Soils at the Academy are primarily derived from granitic parent material. Soils on the sides of ridges are typically coarse and thin, especially in the natural portions of the Academy. Somewhat deeper and finer-textured soils occur at the bases of the ridges. Deeper, more productive soils are found in the floodplain of Monument Creek.

Surface water, wetlands, drainages and riparian areas

The major surface water feature of the Academy is Monument Creek. It rises on the eastern flanks of the Rampart Range about 6 miles northwest of the Academy and flows northeast to the Town of

Palmer Lake, after which it flows south through the Academy on its way to Fountain Creek. There are significant wetlands and riparian areas along Monument Creek, as well as along the other tributary creeks. Wetlands and riparian areas typically occur in floodplains and drainages, which are nearly all classified as “natural” in the Comprehensive Plan for the Academy. Wetlands and riparian areas are considered high-value resource areas.

The area between Palmer Lake and the Academy is rapidly developing. Within the Academy, Goat

Camp Creek, Deadmans Creek, Lehman Run, Douglas Creek, West Monument Creek, and Stanley

Creek flow from west to east and join Monument Creek. Hay Creek joins Monument Creek immediately north of the Academy boundary. Jackson, Black Forest, Smith, Monument Branch, Middle Tributary, Black Squirrel, Elkhorn, Kettle, and Pine Creek flow from east to west and joins

Monument Creek (Figure 3).

Farish contains three man-made lakes and the Academy has five man-made lakes that are heavily used for recreation, mainly fishing. The Farish Recreation Area contains a small fen, which is a type of wetland supported by ground water seepage, and where peat accumulates. The fen harbors the lowest-elevation and eastern-most occurrence in Colorado of a globally rare plant, the Porter feathergrass (Ptilagrostis porteri).

Air Force Academy Integrated Noxious Weed Management Plan 5

Figure 3: Monument Creek and Named Tributaries

6 Colorado Natural Heritage Program © 2015

Plant Communities

The variety of elevation, slope aspect, soils, and soil moisture creates different environments that harbor different plant communities. ESCO Associates Inc. (1992) mapped the plant communities of the Academy. The upland forest vegetation type includes white fir, Douglas-fir, ponderosa pine, Colorado blue spruce, and aspen communities. The upland shrubland vegetation type includes

Gambel’s oak, wax current, skunkbrush, snowberry, and mountain mahogany. The upland grassland vegetation type includes mountain muhly, Parry oatgrass, big and little bluestem, blue grama, western wheatgrass, prairie sandreed, and needle-and-thread communities.

Wildlife

The forest, woodland, shrubland, and grassland habitats at lower and higher elevations support a large diversity of animals including Mule deer, White-tailed deer, American elk, Coyote, and Black bear. The Academy hosts many migratory and non-migratory bird species. Bats, prairie dogs, mice, squirrels, rabbits and a variety of smaller mammals are present at the Academy and Farish.

Rare Plants, Animals, and Significant Plant Communities

The Colorado Natural Heritage Program (2015) has documented 31 species that are considered significant elements at the Academy (Table 1). One species of amphibian, one bird, four insects, two mammals, 10 plant communities and 14 species of rare plants have been documented at the

Academy and Farish Recreation Area (CNHP 2015). There are a number of these elements that are globally vulnerable and imperiled species (G2, G3, T2, T3) and 10 elements that include populations considered to be excellent or very good quality (A or B ranked) occurrences based on population size, quality of surroundings and potential for longevity (Table 1, see Appendix 1 for an explanation of CNHP Element Occurrence Rankings). There are multiple occurrences of these plants, animals and plant communities scattered throughout the natural areas at the Academy and Farish. The

Preble’s meadow jumping mouse is the only species that is Listed Threatened under the Federal

Endangered Species Act. Siemers et al. (2012) conducted a biological inventory that provides detailed locations, photographs and descriptive information for most of the significant elements at the Academy.

Air Force Academy Integrated Noxious Weed Management Plan 7

Table 1. Rare animals, significant plant communities, and rare plants documented at the Air Force Academy and Farish Recreation Area (CNHP 2015). Species are listed by major group, and then according to global and state ranks. (For rank and status definitions please see Appendix 1.)

Common Name Scientific Name Global Rank

State Rank

Federal Status

State Status

Amphibians

Northern Leopard Frog Lithobates pipiens G5 S3 BLM/USFS SC

Birds

Ovenbird B Seiurus aurocapilla G5 S2B

Insects

Hops Feeding Azure Celastrina humulus G2G3 S2

Cross-line Skipper Polites origenes G4G5 S3

A Buckmoth Hemileuca grotei diana G4T3T4 S2

Moss's Elfin B Callophrys mossii schryveri G4T4 S2S3

Mammals

Preble’s Meadow Jumping Mouse Subspecies

A Zapus hudsonius preblei G5T2 S1 LT ST

Gunnison's Prairie Dog - Montane Population Cynomys gunnisoni pop. 1 G5T2 S2 C, BLM

Plant communities

Montane Riparian Shrubland

Alnus incana / Mesic Graminoids Shrubland G3 S2

Great Plains Mixed Grass Prairies (Sandstone/Gravel Breaks)

Schizachyrium scoparium - Bouteloua curtipendula Western Great Plains Herbaceous Vegetation G3 S2

Montane Grasslands

Danthonia parryi Herbaceous Vegetation G3 S3

Mixed Mountain Shrublands

Quercus gambelii - Cercocarpus montanus / (Carex geyeri) Shrubland G3 S3

Thinleaf Alder-Red-osier Dogwood Riparian Shrubland

Alnus incana / Cornus sericea Shrubland G3G4 S3

Narrowleaf Cottonwood Riparian Forests

Populus angustifolia / Salix exigua Woodland G4 S4

Snowberry Shrubland Symphoricarpos occidentalis Shrubland G4G5 S3

Foothills Ponderosa Pine Scrub Woodlands

Pinus ponderosa / Quercus gambelii Woodland G5 S4

Coyote Willow/Mesic Graminoid

Salix exigua / Mesic Graminoids Shrubland G5 S5

Mixed Mountain Shrublands

Cercocarpus montanus / Muhlenbergia montana Shrubland GU S2

Vascular plants a sedge B Carex oreocharis G3 S2

Porter’s feathergrass B Ptilagrostis porteri G2 S2 USFS

Southern Rocky Mountain cinquefoil

Potentilla ambigens G3 S2

8 Colorado Natural Heritage Program © 2015

Common Name Scientific Name Global Rank

State Rank

Federal Status

State Status

Rocky Mountain phacelia Phacelia denticulata G3 S3

New Mexico cliff fern Woodsia neomexicana G4? S2

Frostweed Crocanthemum bicknellii G5 S1

Richardson alum-root Heuchera richardsonii G5 S1

Yellow stargrass Hypoxis hirsuta G5 S1

New England aster Virgulus novae-angliae G5 S1

Dwarf wild indigo Amorpha nana G5 S2

American currant Ribes americanum G5 S2

Prairie violet Viola pedatifida G5 S2

Vernonia (Plains ironweed) Vernonia marginata G5? S1

Gay-feather Liatris ligulistylis G5? S2 A

= At least one A ranked occurrence, = at least one B ranked occurrence

Conservation Areas

There have been a number of studies to identify the significant natural areas of the Academy (ESCO

Associates Inc. 1992, Ripley 1994, CNHP 1995, Ellingson et al. 1996) and most recently a biological inventory conducted by CNHP in 2012 (Siemers et al. 2012). About 40 counties in Colorado have been surveyed by the Colorado Natural Heritage Program for critical biological resources (CNHP

2015), and El Paso County was surveyed in 2001 (Doyle et al. 2001). Locations with Natural

Heritage significance (where significant elements of biodiversity have been documented) are presented in survey results as Potential Conservation Areas (PCAs). The goal of delineating PCAs is to identify a land area that can provide the habitat and ecological needs upon which a particular element or suite of elements (rare plants, animals and plant communities) depends upon for their continued existence. PCAs are ranked according to their biodiversity significance or B ranks (Table

2).

Table 2. Biodiversity Ranks and Definitions

The Colorado Natural Heritage Program (CNHP 2015) has identified five Potential Conservation

Areas or PCA planning areas for the protection of the rare plant and animal species and high quality plant communities at the Academy and Farish (Table 3, Figures 4 & 5). Detailed profiles for each of these PCAs can be found in Appendix 2. Since the last weed management plan was updated and since the 2012 biological resources inventory (Siemers et al. 2012), new Element Occurrence

Records (EORs) have been documented and a new PCA was described (Figure 4).

B1 Outstanding Significance (irreplaceable)

B2 Very High Significance

B3 High Significance

B4 Moderate Significance

B5 General or State-wide Biological Diversity Significance

Air Force Academy Integrated Noxious Weed Management Plan 9

Table 3. List of Potential Conservation Areas at the Academy and Farish

PCA Name Biodiversity Rank

Monument Creek B2

Farish Recreation Area B3

Air Force Academy Oak Foothills B3

I-25 Shamrock* B5

Pine Drive B4

*PCA added since 2012 Inventory (Siemers 2012).

Figure 4. Potential Conservation Areas (PCAs) at Farish Recreation Area.

10 Colorado Natural Heritage Program © 2015

Figure 5. Location of Five Potential Conservation Areas (PCAs) and New Element Occurrences (EORs) at the Air Force Academy in 2015

Air Force Academy Integrated Noxious Weed Management Plan 11

1.3 Noxious Weed Legislation

There are a variety of federal, state, and local laws or regulations regarding noxious weed control that pertain to the US Air Force Academy in Colorado. These are listed below along with a brief description of the U.S. Air Force Academy and Farish Recreation Area Natural Resource

Management Plans.

Sikes Act

The Sikes Act (16 USC 670a-670o, 74 Stat. 1052, Public Law 86-797 as amended) of 1960 provides for cooperation by the Departments of the Interior and Defense with appropriate State agencies “to promote effectual planning, development, maintenance, and coordination of wildlife, fish, and game conservation and rehabilitation in military reservations.” The emphasis on conservation of natural resources on military reservations lays the framework for Department of Defense management of noxious weeds, in context with subsequent legislation.

Federal Noxious Weed Act

The Federal Noxious Weed Act of 1975 (Public Law 93-629 7 U.S.C. 2801 et seq.; 88 Stat. 2148) established a Federal program to control the spread of noxious weeds. Section 1453 of the 1990

Farm Bill (Public Law 101-624) added Section 15 to the Act establishing provisions for the management of undesirable plants on Federal lands. Undesirable plant species are defined as

“plant species that are classified as undesirable, noxious, harmful, exotic, injurious, or poisonous pursuant to State or Federal law.” Undesirable species cannot include federally listed threatened or endangered species or species indigenous to the area in question.

Where state or private programs for the control of noxious weeds exist, federal land-managing agencies are required to:

1. Designate an office or person adequately trained in managing undesirable plant species to develop and coordinate a program to control such plants on the agency's land;

2. Establish and adequately fund the undesirable plant management program through the agency's budget process.

3. Complete and implement cooperative agreements with the States regarding the management of undesirable plants on agency land. These agreements shall prioritize and target the undesirable plant species to be controlled or contained, describe the integrated management system to be used in control or containment, define the means of implementation, define the duties of the respective agencies, and establish a timeline for completion of the plan.

4. Establish integrated management systems to control or contain undesirable plants targeted under the cooperative agreements. Such integrated management systems shall use an interdisciplinary approach that includes participation by experienced federal or state agency personnel and consideration of the most efficient and effective method of containing or controlling the undesirable plant species, scientific evidence and current technology, the physiology and habitat of a plant species, and the economic, social, and ecological consequences of implementing the program.

12 Colorado Natural Heritage Program © 2015

Executive Order 13112

Executive Order 13112, signed in February 1999, directed Federal agencies to identify agency actions that may affect the status of invasive species, and, as applicable, to:

1. prevent introduction of invasive species;

2. detect and respond rapidly to and control populations of such species in a cost-effective and environmentally sound manner;

3. monitor invasive species populations accurately and reliably;

4. provide for restoration of native species and habitat conditions in ecosystems that have been invaded;

5. conduct research on invasive species and develop technologies to prevent introduction and provide for environmentally sound control of invasive species; and

6. promote public education on invasive species and the means to address them.

Federal agencies are further forbidden to authorize, fund, or carry out actions that are likely to cause or promote the introduction or spread of invasive species in the United States or elsewhere unless the agency has determined and made public its determination that the benefits of such actions clearly outweigh the potential harm caused by invasive species; and that all feasible and prudent measures to minimize risk of harm will be taken in conjunction with the actions. The Executive Order also created an Invasive Species Council and an Invasive Species

Advisory Committee to provide national leadership on invasive species issues and to develop a nation-wide Invasive Species Management Plan.

U.S. Air Force Regulatory Requirements

Air Force Instruction 32-7064 (Integrated Natural Resource Management) requires the control of noxious, exotic, and invasive species. Air Force agricultural outgrant programs must comply with the requirements of the Federal Noxious Weed Control Act. Outgrant programs will, to the extent practicable and within the limits of available funds, support state and federal programs for the control of noxious, exotic, and invasive plant species. Installations may enter into cooperative agreements with local area government entities that establish integrated pest management principles for the control of undesirable plant species. Expenditure of agricultural program funds to control noxious, exotic and invasive species will be consistent with the level of effort exhibited on similar federal, state or private agriculture and grazing lands in the vicinity of the installation.

Colorado Noxious Weed Act

In 1990, the Colorado General Assembly passed House Bill 90-1175, adding article 5.5 (Undesirable

Plant Management) to Title 35 of the Colorado Revised Statutes. Originally known as the “Colorado

Weed Management Act,” this legislation defined the duty and authority of county and municipal governments to control noxious weeds, and required the adoption of management plans for undesirable plants for all such governing bodies. The Act authorizes local governing bodies of all counties and municipalities in Colorado to enter into cooperative agreements with federal and state agencies for the integrated management of noxious weeds within their respective territorial jurisdictions. In 1996 House Bill 96-1008 renamed and amended this Article as the “Colorado

Noxious Weed Act,” to establish and fund an office of state weed coordinator, and to institute the

Air Force Academy Integrated Noxious Weed Management Plan 13 designation by rule of state and local noxious weed lists. Rules pertaining to the administration and enforcement of the Act, including the list of designated noxious weeds are published under the Code of Colorado Regulations (8 CCR 1206-2). The Act was further amended in 2003, codifying the classification of designated weeds. The commissioner of the Colorado Department of Agriculture is directed to develop and implement by rule state noxious weed management plans, including management objectives for noxious weed species classified as list A or list B species.

The Colorado 2014 Weed List provides prioritized management goals for the listed weeds (List A, B, and C - Table 4), per rules promulgated by the Colorado Department of Agriculture and applicable as of December 30, 2014, pursuant to revisions of the Colorado Weed Management Act enacted in 2003.

The Colorado Noxious Weed Act (2003), specifies that certain noxious weeds must be eradicated

(List A species), while others (List C species) will no longer be mandated for control by the State

(Table 4). Management plans/rules prepared by the State for the List B species (which includes all of the worst noxious weeds mapped at the Academy and Farish, except for field bindweed), mandates whether eradication, suppression, or containment will be required depending on location.

Table 4. List A, B, C and Watch List Definitions (Colorado Noxious Weed Act, 35-5.5-104.5 to 35.5-118)

El Paso County Weed Management Program

El Paso County updated their Noxious Weed Management Plan in 2014:

http://car.elpasoco.com/clerktotheboard/Documents/14-097.pdf

The County has adopted an ordinance that regulates the management of undesirable plants on private and public lands within the County. The ordinance requires certain plant species that are listed as “undesirable” to be managed within the unincorporated portions of the County. The undesirable plants include leafy spurge, diffuse knapweed, Russian knapweed, spotted knapweed, Canada thistle, and purple loosestrife. In addition, musk thistle and yellow toadflax are designated as potentially undesirable. All of these species are known to occur on the Academy, except for purple loosestrife. The commissioners’ call for 1) preventing noxious weeds from entering non-

List A species are invasive weeds that are either not known to occur in Colorado or are of very limited distribution and are required to be eradicated (completely eliminated).

List B species are invasive weeds with populations of varying distribution and densities within the state. The level of mandated control is based on local conditions.

These weeds may require eradication within certain areas of the state.

List C species are widespread and common within the state. They may pose a risk to agricultural lands and may be required to be controlled.

Watch List species that are not known but that are expected to be found in Colorado and should be reported when found.

http://car.elpasoco.com/clerktotheboard/Documents/14-097.pdf

14 Colorado Natural Heritage Program © 2015 infested sites, 2) developing and maintaining a noxious weed inventory and monitoring to assess progress, 3) educating the public and 4) researching weed management control strategies.

Website for County Noxious Weeds http://adm.elpasoco.com/Environmental%20Division/Forestry%20and%20Noxious%20Weeds/P ages/default.aspx

1.4 Past and on-going weed management at the U.S. Air Force Academy

Noxious weed surveys and species-specific noxious weed monitoring has been conducted by the

Colorado Natural Heritage Program at Colorado State University over the past 15 years (Rondeau and Lavender 2012, Rondeau et al. 2015). Noxious weed control actions employed at the Academy have included the broad use of biocontrol insects and herbicide applications, with localized hand-pulling and digging.

Biocontrol

Dr. Jerry Michels, formerly a researcher with the Texas Agricultural Experiment Station (Texas

AgriLife) in Bushland, Texas, oversaw a research biocontrol project at several federal installations in Colorado, including the Academy (Michels at al. 2003 - 2014). This project began in 2000 at the

Academy and continued through 2014. Biocontrol agents have shown some success in controlling diffuse and spotted knapweeds, and leafy spurge at the Academy. Biocontrol insects have been introduced to control St. Johnswort (which has been very successful elsewhere and at the Academy) and Canada thistle (which has not been particularly successful elsewhere). In addition, musk thistle is probably being controlled to some degree by a weevil that has been widely introduced in

Colorado and is now essentially naturalized. Surveys performed in 2014 for biocontrol agents occurring outside their original release site indicated that most insects have naturally dispersed throughout the Academy to other dense populations of the target weeds.

Herbicides

Herbicides have been widely used at the Academy to control a variety of noxious weeds, especially leafy spurge, diffuse and spotted knapweeds, Russian knapweed, St. Johnswort, teasel, Scotch thistle, musk thistle, Canada thistle, bouncingbet, Russian olive, yellow spring bedstraw, and others.

The Academy annually contracts for herbicide application for up to 450 acres of noxious weed infested rangeland and forest. Frequently used herbicide active ingredient includes aminopyralid, 2-4-D amine salt, imazapic, metsulfuron, and triclopyr.

Mechanical Removal

Hand pulling and cutting has been done for a variety of species at the Academy that have a very low cover. Dalmatian toadflax, myrtle spurge, salt cedar (tamarisk), houndstongue, bouncingbet and

Scotch thistle plants have been treated with some success by pulling or cutting plants. This method has been an excellent early detection rapid response technique that has been used for years at the

Academy to help control these species.

http://adm.elpasoco.com/Environmental%20Division/Forestry%20and%20Noxious%20Weeds/Pages/default.aspx http://adm.elpasoco.com/Environmental%20Division/Forestry%20and%20Noxious%20Weeds/Pages/default.aspx

Air Force Academy Integrated Noxious Weed Management Plan 15

2.0 TARGET WEED SPECIES 2015

The 20 weed species targeted for this plan are based on the Colorado Department of Agriculture

Noxious Weed List (Code of Colorado Regulations 2014), the 2004 U.S. Air Force Academy and

Farish Recreation Area Integrated Noxious Weed Management Plan (Carpenter and Perce 2004), weed mapping conducted by CNHP (Rondeau and Lavender 2012) and communications with the

Academy (pers. comm. Brian Mihlbachler 2014). The target list includes 17 species on the Colorado

State Noxious Weed List (1 List A, 15 List B and 1 List C) and three species of garden escapes or planted ornamentals that are not on the State Weed List, but are actively managed, or being considered for active management at the Academy due to their potential to be invasive (Table 5).

Some species are managed opportunistically, that is, they are treated as they are encountered by

Academy staff. Cheatgrass and common mullein were targeted in the 2004 plan but are not a focus in the 2015 management plan due to the widespread nature of these species (Table 5). Field bindweed, chicory and common burdock are all state List C noxious weeds that were not included in the 2004 management plan. These species will again not be included in 2015 due to the widespread distribution and relatively low potential for impacts compared to other species (Table

5). Field bindweed was surveyed and biocontrol agents were introduced, however, the results did not appear to show successful treatment (Michaels et al. 2014).

Since the 2004 weed management plan (Carpenter and Perce 2004) was written, the Colorado State

Noxious weed list was updated (CCR 2014) with the following new changes:

Hairy willowherb (Epilobium hirsutum) was moved to List A from Watch List status and garden yellow loosestrife (Lysmachia vulgaris) was added to List A. Although neither of these species has been documented at the Academy, there is potential habitat especially along the creeks. We recommend the staff learn to identify, understand the plant biology and be prepared for effective early detection and rapid response actions for these species.

Two List B species that also are not currently known from the Academy, spurred anoda

(Anoda cristata), and Venice mallow (Hibiscus trionum), were removed from the State

Noxious Weed List. No action is required on the part of the Academy for this change.

Quackgrass (Elymus repens) is known from the Academy, and has moved from List B to

List C. This also will not require any action on the part of the Academy, which was not currently targeting this species for management.

A change was made by CNHP to combine diffuse and spotted knapweeds (Centaurea diffusa, C.

maculosa) and a hybrid of these two species for monitoring and mapping purposes. This was necessary because of rampant hybridization at the Academy (Rondeau and Lavender 2012).

These knapweeds will also be considered as a single management group for this plan (note: this group does not include Russian knapweed (Acroptilon repens).

16 Colorado Natural Heritage Program © 2015

Table 5. List of Noxious Weeds documented at the Academy and Farish as of 2014 (Rondeau and Lavender-

Greenwell 2014). The list also includes three additional weed species that are not on the State Weed List, but are actively managed or being considered for active management. Shaded and bolded species are the focus of this management plan.

Common Name

Latin Name

Colorado Weed List

Current Management

Myrtle spurge Euphorbia myrsinites A Rapid response Bouncingbet Saponaria officinalis B Rapid response

Bull thistle* Cirsium vulgare B Active management

Canada thistle* Cirsium arvense B Active management Common teasel* Dipsacus fullonum B Opportunistic management Dalmatian toadflax Linaria dalmatica B Rapid response Dame’s rocket Hesperis matronalis B Rapid response Hoary cress (Whitetop)*

Cardaria draba B Active management

Houndstongue Cynoglossum officinale B Rapid response Knapweeds (spotted, diffuse and hybrid)*

Centaurea spp. B Active management

Leafy spurge* Euphorbia esula B Active management Musk thistle* Carduus nutans B Active management Russian knapweed* Acroptilon repens B Active management Russian olive* Elaeagnus angustifolia B Active management

Scotch thistle* Onopordum acanthium

B Active management

Yellow toadflax* Linaria vulgaris B Opportunistic management Salt cedar (Tamarisk) Tamarix ramosissma B Rapid response Chicory Chichorium intybus C Not managed Common burdock Arctium minus C Not managed Common mullein* Verbascum thapsus C Not managed Common St.

Johnswort*

Hypericum perforatum C Active management

Downy brome (cheatgrass)*

Bromus tectorum C Not managed

Field bindweed Convolvulus arvensis C Not managed Poison hemlock Conium maculatum C Not managed Quackgrass Elymus repens C Not managed Wild proso millet Panicum miliaceum C Not managed Siberian peashrub Caragana arborescens NA Considering for management Tatarian honeysuckle Lonicera tatarica NA Opportunistic management Yellow spring bedstraw Gallium verum NA Rapid response

*Weed species included in the 2004 Weed Management Plan.

Air Force Academy Integrated Noxious Weed Management Plan 17

2.1 Priorities for Weed Management

The Colorado Natural Heritage Program weed survey (Rondeau and Lavender 2012) mapped 8,308 occurrences of seventeen noxious weed species, and two additional weed species of concern.

Controlling this number of weed occurrences is not practical and additional weed locations at the

Academy and Farish are likely present that have not yet been detected. Thus, it is imperative to prioritize specific plant species and specific areas for control. Sources used to prioritize weeds and weed management areas include the 2004 Weed Management Plan (Carpenter and Perce 2004), weed mapping and weed monitoring information (Anderson et al. 2003, 2009, Anderson and

Lavender 2006, 2007, 2008a, 2008b, Rondeau et al. 2010, 2011, 2015, Rondeau and Lavender, 2012, 2013, 2014), Heibert and Stubbendieck (1993), the Biodiversity Tracking and Conservation

System (BIOTICS) database (CNHP 2015), and Invasive Species Impact Ranks (I ranks) of Morse et

al. (2004). The Invasive Species Assessment Protocol (Morse et al. 2004, NatureServe 2015) has been used to provide up-to-date information about ecological impacts, distribution, trends, and management issues for noxious weeds throughout the U.S.

Priority Species

The primary factors considered for 20 weed species targeted in this plan (Table 5) were: 1) the extent of the infestation, and 2) the feasibility of successful control and 3) the location or proximity to conservation elements.

1. The extent of an infestation is reported in terms of the occupied acres that have been mapped at the Academy (Rondeau and Greenwell 2012), as well as communication with Brian Mihlbachler. Because acreage alone does not fully portray the problem posed by weed infestations, density of the plants in the infestations is considered when available.

2. The feasibility or likelihood of successful control,…