Preliminary observations on pollinator diversity and attractiveness to different ornamental plants were conducted at the arboretum of the Palomar College by six students and two teacher assistants participating in the STEM Academies program during the Summer of 2017.
Material and Methods
Study Site. The study was conducted at Palomar College, located at 1140 West Mission Rd., in San Marcos California (33o08’56.9” N, 117 o11’11.1” W). Insects visiting plants with open flowers were observed, collected and photographed, during the month of July.
Pollinator Diversity. To study the diversity of pollinators, flower visitors were collected from 7/6/17 to 7/11/17 using a net or a Nature Bound Bug Vacuum. The specimens collected were frozen, sorted, pinned and identified to the lowest taxonomic level possible. Insect display boxes with the specimens collected in selected plants were prepared.
Pollinator Attractiveness to selected plants. To compare the diversity and abundance of the insects attracted to a California native plant and a non-native ornamental, visual observations to clusters of flowers of Laurel Sumac (Malosma laurina) and Yellow trumpet bush (Tecoma stans) were conducted by four student observers and two teacher assistants. The number of honey bees, bumble bees and small bees or other insects were recorded on randomly selected branches of nine small trees of Yellow trumpet bush and three shrubs of Laurel Sumac. The clusters of flowers were observed for one minute on 7/5/17 and 7/6/17 every two hours, from 9:00 am to 3:00 pm.
Our preliminary observations on the diversity and abundance of honey bees, bumble bees and small bees or other insects visiting T. stans and M. laurina during 7/5/17 and 7/6/17 and suggest the following trends:
Tecoma stans attracted a greater number of honey bees than Malosma laurina at 9:00 am, but there were no significant differences in the number of honey bees recorded in T. stans and M. laurina at 11:00 am, 13:00 pm and 15:00 pm.
Bumble bees visited T. stans but were not seen visiting M. laurina.M. laurina attracted a larger number of small bees than T. stans at 9:00 am. However, the number of small bees or other insects attracted to M. laurina tended to decrease from 9:00 am to 3:00 pm
Researcher: Dr. James Bethke