Promoting native plants for pollinators and monarchs in the Arboretum

Work in the Spencer J. Roemer Arboretum this summer has been aimed at improving its value for native pollinators like bees, butterflies, and other insects – as well as for showing off the beauty of native plants. Native pollinators have suffered population declines because of habitat loss and fragmentation, habitat degradation through the spread of invasive species, and pesticide use. Three-quarters of flowering plants require animal pollinators to some degree to reproduce, and animal pollinators aid in production of 35% of the world’s crops.

This spring we planted a variety of native species in the garden surrounding the gazebo, selected to provide nectar throughout the growing season. Plants like wild columbine and golden groundsel flower early in the summer, beebalm and butterfly milkweed show up in mid-summer, and joe-pye weed, boneset, and ironweed add color in late summer and into the fall. 

 

Student Arboretum assistants planting gazebo garden in May.

Some native plants added to the gazebo garden this year (clockwise from top left):  wild colombine, heartleaf golden alexanders, scarlet bee-balm, joe-pye weed, anise hyssop, boneset.

The gazebo garden serves as a showcase for native plants that are both aesthetically pleasing and valuable to insect visitors. In the south end of the Arboretum we have started a project to restore the former site of a community garden to native meadow habitat that will provide both food and shelter to native insect pollinators. 

The restoration project began with mowing the existing vegetation in the site, largely non-native weedy species, thanks to volunteer effort of ’72 alumnus John Wolf who brought his 50-year old Gravely mower to do the job. Our arboretum assistants accumulated and distributed cardboard to smother the ground and suppress growth and seed germination of existing plants. 

Site before preparation (top left), John Wolf mowing down existing vegetation (top right), site after mowing (bottom left), Arboretum assistants spreading cardboard to smother vegetation (bottom right).

Then through the generosity of Jon and Priscilla Titus (who have a thriving yard in Fredonia full of native plants to spare), we obtained a variety of species to plant in the cracks between the cardboard pieces to get the meadow started. (Jon is Associate Professor of Biology at SUNY Fredonia, and Priscilla is an environmental consultant.) Our first plantings were done on June 28, and another batch were added on August 24. This fall we will try to cover the site with leaf mulch. The hope is that the cardboard will break down over winter and our summer plantings will have a head start on non-native weeds that might return to the site. We will also be gathering seeds from natives to sow in the site and to start as seedlings to plant in the spring. The development of a native-dominated meadow will take time, but should enhance the diversity of the Arboretum and its quality as habitat for wildlife. (And I would love to expand this flora into no-mow zones around the Arboretum.)

Plantings in the native plant meadow restoration project. Clockwise from top left: student assistants weeding and planting, Jerusalem artichoke, New York ironweed, cutleaf coneflower.

In addition to adding natives for insect pollinators in general, we are also planting milkweeds, the host plant for monarch butterflies that have recently experienced population declines. Our four swamp milkweeds planted this year in the gazebo garden are supporting many monarch larvae, and the existing large butterfly milkweeds at the Arboretum entrance also fed caterpillars. We planted milkweed seeds at the beginning of the summer and recently planted these seedlings in several locations in the Arboretum, including the native plant meadow. With the success of these plantings and more to come, we hope the Arboretum can contribute to restoring habitat for this iconic animal.

Monarch adult investigating a milkweed plant (left); egg laid on swamp milkweed flower buds (right).

Top: monarch larvae on swamp milkweed in gazebo garden; Bottom:  monarch larvae on butterfly milkweed in Arboretum entrance garden.

Arboretum assistants planting milkweed seedlings. From left:  Emma Witherwax, Julian Koob, Josh Backhaus.

More information about Arboretum activities and natural history can be seen at our Facebook page:  https://www.facebook.com/RoemerArboretum.