Use of Perennial and Annual Flowers to Attract Beneficial Insects to Alfalfa

M. Benander1 and R. Jabbour1

Intensification of cropland has lowered habitat beneficial insects. Specifically, we are comparing diversity in agricultural landscapes, leading to whether insect groups vary between habitats of fewer alternative resources for natural enemies annual flower mix, perennial flower mix, alfalfa, of agricultural pests. Natural enemies represent and a control of fescue grass. an important mechanism to reduce pest popula- Materials and Methods tions and improve crop yields. Alternative habi- tats near or bordering agricultural fields can The field site for this experiment is located at provide overwintering habitat, refuge from the James C. Hageman Sustainable Agriculture management disturbances, and additional food Research and Extension Center (SAREC) near sources important for many types of natural Lingle. Plots (25 ft by 25 ft) of alfalfa were adja- enemies. Alfalfa weevil and aphids are major cent to either a perennial flower strip, an annual pests of alfalfa hay in Wyoming. Beneficial in- flower strip, or a control strip of fescue grass. sects that can kill these pests also require alter- The species used for each treatment from 2014 nate resources such as flower nectar to survive. are listed in Tables 1 and 2. Perennial species These beneficial insects may increase their pest were sourced regionally when possible. Plots control activities in response to increased flower and treatments were then vacuum sampled and resources. the collected arthropods counted and sorted. Objectives Results and Discussion We are testing whether planting strips of peren- Because this was an establishment year, not all nial and annual flowers in alfalfa fields attract flowers in the perennial treatment bloomed,

Figure 1. Relationships between average number of individual lady beetles and habitat types.

1Department of Plant Sciences.

2015 Field Days Bulletin | 87

Table 1. Annual species used in flowering strips. Table 2. Perennial species used in flowering strips.

Common Name Species Common Name Species Lacy phacelia Phacelia tanacetifolia Blanketflower Gaillardia aristata Common sunflower Helianthus annuus Sticky geranium Geranium viscosissimum Cosmos Cosmos bipinnatus Yellow penstemon Penstemon confertus Bluebells Phacelia campanularia Wild beebalm Monarda fistulosa Rocky Mountain beeplant Cleome serrulata Hairy false goldenaster Heterotheca villosa Plains coreopsis Coreopsis tinctoria Harebells Campanula rotundifolia Dill Anethum graveolens Showy fleabane Erigeron speciosus Pot marigold Calendula officinalis Prairie sunflower Helianthus maximiliani Cornflower Centaurea cyanus Sainfoin Onobrychis viciifolia

and vacuum sampling only occurred toward the Acknowledgments: We are grateful to Bob Baum- end of the season. We present data from the gartner and the SAREC field crew, Jackson Bassett, sampling data of August 11, 2014. Following Matthew Cozzens, Bill Stump, David Leitz, and our initial sort, we determined that lady beetles Seth Gill for assistance in establishing and maintain- ing field experiment plots. Casey Delphia and Brett were attracted to both annual and perennial Blauww advised on experimental design. flowering strips (Figure 1). We are repeating our sampling over the entire growing season Contact: Randa Jabbour at [email protected] or this year, rather than just one sampling date, to 307-766-3439. determine whether this pattern occurs more Keywords: alfalfa, biological pest control, broadly. flowering strips PARP: I:1,2, X:2

88 | 2015 Field Days Bulletin