
Project description
Squash, pumpkin, and gourd crops (genus: Cucurbita) were among the first crops domesticated in the Americas. These plants are pollinator-dependent because they have separate male and female flowers that require insects to move pollen from anthers to stigmas to produce high-quality fruits. The large yellow Cucurbita flowers support a diverse community of bee pollinators including honey bees, bumble bees, carpenter bees, and the highly specialized squash bees. Before the domestication and widespread cultivation of Cucurbita crops, squash plants were not found in the northern latitudes of North America, neither were squash bees. However, now both bees and plants are widespread and these plant-pollinator systems have been poorly characterized in most of these areas.
In this project, we will utilize the experience, knowledge, and dedication of community scientists (entomologists, botanists, ecologists, gardeners) to plant and grow wild and domesticated pumpkins, squashes and gourds (genus Cucurbita) to compare the attractiveness of their flowers to bee pollinators. Participants will receive seeds of three species of Cucurbita: C. pepo (cultivated), C. maxima (cultivated), and C. foetidissima (wild) and plant these seeds in raised beds in their own gardens over the summer. During the flowering period of the plants, participants will collect data for 10 minutes weekly on male and female flowers and collect bee species visiting them. Collected bees will then be returned to the López-Uribe Lab at Penn State University in University Park, PA for pinning and identification. All the data collected for this project will be made publicly available through SCAN and GBIF.
Project goals
- Gain a better understanding of the variation in the pollination community of pumpkins, squashes and gourds across North America
- Identify differences in bee preferences for domesticated and wild Cucurbita species
- Document the distribution of squash bee specialists (Eucera (Peponapis) and Xenoglossa) across North America
- Engage project participants in scientific research through data collection, and the importance of bee pollination for food production
Instructional video explaining data collection methods
Participants
Our goal is to recruit 1-2 volunteers from several states across the United States. We want to prioritize states that have a diversity of squash bees.
If you are interested in participating please email Sarah Kania at sek5555@psu.edu
2024 Results

Click here to view the full 2024 report
2023 Results
From our pilot study a total of 98 bees from 4 species were collected.
- Eastern bumble bee (Bombus impatiens) – 51 specimens
- Squash bee (Xenoglossa pruinosa) – 31 specimens
- Honey bee (Apis mellifera) – 12 specimens
- Green sweat bee (Augochlora pura) – 2 specimens
By plant:
- ‘Black beauty’ zucchini (Cucurbita pepo) – 57 bees
- ‘Lumina’ pumpkin (Cucurbita maxima) – 41 bees
By county:
- Allegheny County, PA – 13 bees
- Susquehanna County, PA – 21 bees
- Warren County, PA – 64 bees

![]() | This project is funded by the NSF CAREER Award (DEB-2046474). |
