We recently created an Urban Habitat Assessment tool, designed to help you see your yard through the eyes of a pollinator, identify areas for improvement, and prioritize actions you can take to promote these insects in your yard and community.
As we all adjust to physical distancing, shelter-in-place mandates, and other recent changes related to the coronavirus, our own yards and neighborhood green spaces can be more important than ever for stress-relief and well-being. Thankfully, urban, suburban, and rural yards can be excellent places to support wildlife, while also providing recreation and food for ourselves and our families.
Pollinators are one of the easiest groups of declining animals to support in a residential landscape, since even small spaces have the potential to meet the most basic needs of the entire insect life cycle—and even simple changes to our landscaping can make a huge difference to these animals.
Here at the Xerces Society, we recently created an Urban Habitat Assessment tool, designed to help you see your yard through the eyes of a pollinator, identify areas for improvement, and prioritize actions you can take to promote these insects in your yard and community. This guide is intended for assessing an average urban/suburban lot, but can be used for larger or smaller sites.
Figure 1: Completing a pollinator habitat assessment for your yard can be a great way to prioritize actions and monitor improvements over time. (Graphic design: Xerces Society / Sara Morris; Photos: Xerces Society / Jessa Kay Cruz)
On larger sites, it may make sense to assess sections individually rather than altogether. If you live in an apartment complex and don’t have a “yard,” try completing the guide for the entire property, including balconies and other green spaces. When combined, the ledges/balconies of several apartments can add up to significant foraging and nesting habitat—just be sure to follow your local guidance on physical distancing (you can always call or email neighbors for their input).
Let’s get started. The assessment tool will guide you through each of the key resource concerns of pollinators, starting with flowering habitat. As you walk around your yard (or look at a satellite image in Google Maps), make note of what percentage of your yard is covered in flowering vegetation (e.g., flowering trees, fruit-bearing shrubs, vegetable gardens, flower beds), as opposed to non-flowering vegetation (mowed lawn, conifers, wood chip mulch, etc.).
Figure 2: This California yard was transformed from mowed lawn with very little wildlife value to a diverse, colorful haven for pollinators and other wildlife. (Photos: Xerces Society / Jessa Kay Cruz)
Next, assess what percentage of your flowering vegetation is native; i.e., plants that have a very long history of naturally occurring in the wild ecosystems of your area, pre-European settlement of the Americas. Although pollinators may find some nutritional value from non-native plants, native plants do the best job of supporting the widest array of native pollinators, given their long co-evolutionary history. In fact, roughly one-third of bee species will only collect pollen from particular native plants. Similarly, many butterflies and moths depend on the leaves of specific host plants, typically native, for their young to eat (the dependency of monarchs [Danaus plexippus] on milkweed [Asclepias spp.] is a well-known example).
On the back page of the guide you’ll find a table listing a variety of plant genera for each region, with icons for each of the following categories:
- Plants that provide food for specialist bees with strict preferences for certain types of pollen.
- Host plants for butterfly and moth caterpillars.
- Pollinator "superfoods," that is, plants that provide exceptional forage for a wide variety of bees and other pollinators.
Think creatively about how you can add more native vegetation to your yard, perhaps by converting an area of lawn to native wildflowers (Figure 2), or by planting a hedge of native shrubs along a property border. If space is really limited, maybe it’s time to remove that border of daylilies (Hemerocallis spp.) and replace it with a variety of native flowers that provide higher-quality food for pollinators and bloom in succession throughout the growing season.
Figure 3: Native wildflowers, blueberry (Vaccinium sp.) bushes, and apple (Malus sp.) trees provide high-quality food for pollinators, songbirds, and people in a small yard in northern Minnesota. (Photo: Xerces Society / Sarah Foltz Jordan)
Speaking of season-long bloom, as you complete the form, you’ll be asked to estimate the number of species you have that bloom during each season. This is important because different pollinators are active (and therefore hungry) during different parts of the year. Make a list of all the plants in your yard that provide flowers (including flowering trees, garden plants, perennials, annuals, natives and non-natives), along with an estimate of when they bloom.
You might not know this off-hand; that’s OK! It helps to mark up a calendar over the growing season as different plants come in and out of bloom, or take frequent pictures of your yard to record bloom time. Often, spring or fall bloom is most limited, although every yard is different! Once you have identified your own yard’s bloom gaps, check with a local nursery or Xerces plant lists to find wildflowers or shrubs that might help you fill those intervals.
Along with flowers, the availability of nesting and overwintering habitat is one of the most important factors influencing populations of native bees and other beneficial insects. Yet, traditional “manicured” landscaping practices rarely leave enough natural areas to support nesting. Native bees nest and overwinter in a variety of places. Roughly 70% nest in the ground, and about 30% nest in cavities in dead wood, branches, and plant stems, such as the canes of pruned raspberry bushes (Rubus spp.), shown in Figure 4.
Figure 4: Edible landscaping is a great way to provide for pollinators and meet some of your own food needs all in one space! This raspberry hedge provides excellent nesting habitat for a variety of insects (above), along with abundant edible fruit, and blossoms in springtime when pollen and nectar resources might be limited. (Photos: Xerces Society / Sara Morris)
Figure 5: To benefit stem-nesting insects, we recommend leaving your flower gardens intact over the winter, and pruning them back in spring at heights of 6–12 inches. As you prune, you are creating new nesting sites for bees—like small carpenter bees (Ceratina spp., B). (Photos: A: Xerces Society / Sarah Foltz Jordan, B: Heather Holm)
Bumble bee (Bombus spp.) nests are often found under woody plants, tall grasses, brush piles, rock piles, or hidden among vegetation. Many insects, including some butterflies, moths, beetles, hoverflies, and queen bumble bees, overwinter underneath leaf litter, in the duff layer of forests, or under loose soils. Diverse habitat features on your site will increase the likelihood of nesting and overwintering success. Here are seven things your yard should have (in no particular order):
- Stem stubble (see photo below).
- Places with bare soil or patchy vegetation.
- Leaf litter.
- Shrubs and bushes pruned to create nest entrances.
- Brush piles, logs, and stumps.
- Rock piles or rock edging (e.g., low retaining walls).
- Overgrown, unmown grassy areas (ideally with native bunchgrasses).
Not surprisingly, the use of pesticides in lawns, gardens, and landscaping can have negative impacts on pollinator populations. As you go through the assessment guide, you’ll see that points are awarded for a variety of practices, including avoiding pesticide products and purchasing landscaping plants that have not been treated with neonicotinoids or similar chemicals.
Figure 6: Abundant natural areas and wildflower landscaping in your neighborhood can help facilitate the movement of pollinators from one patch of habitat to another, and increase the likelihood that they will have enough food and nesting sites to build healthy populations. (Graphic Design: Xerces Society / Sara Morris. Photos, clockwise from lower left: Xerces Society / Sara Morris ["Cavity-Nesting Bee"], Xerces Society / Sarah Foltz Jordan , Xerces Society / Nancy Lee Adamson , Dustin Demmer / Blazing Star Gardens, LLC [3, 4, and 5], Xerces Society / Matthew Shepherd ["Ground Nesting Bees"], ‘Dustin Demmer / Blazing Star Gardens, LLC , Xerces Society / Matthew Shepherd , Stephen Thomforde , Dustin Demmer / Blazing Star Gardens, LLC . Overarching image of residential development: Will Parson, Chesapeake Bay Program / Flickr Creative Commons)
Finally, let’s consider the landscape context of your yard. In other words, where is your yard situated in the broader landscape? If you are in a highly developed area, your habitat is more critical than ever for providing the basic needs of the insects remaining in your area. If there are parks or natural areas nearby, your own contribution can be valuable in connecting habitat fragments and fostering movement, growth, and resilience in local pollinator populations. Our action checklist offers a variety of ways to increase habitat connectivity for pollinators by building knowledge and enthusiasm for pollinators in your neighborhood—while honoring physical distancing guidelines:
- Participate in Bumble Bee Watch.
- Install a habitat sign.
- Start an application for your town, city, college, or university to become a Bee City USA or Bee Campus USA.
Even in the midst of this global humanitarian crisis, many people are looking for ways to make a personal impact on the environment from home. We hope that having a few fun and meaningful projects to work on in our own yards can be a welcome relief from the stress and chaos around us, as you and your loved ones do your best to stay safe and healthy through this difficult time.