How to Attract Pollinators

The vast majority of native bees build nests underground, about 2800 species.  There are several species of bees that are ground dwelling, each of which have different styles of nest building.  When it comes to creating the conditions to allow ground dwelling bees to create their nesting areas, they need to have direct access to the soil.  By allowing parts of the landscape remain with bare soil can make an impact.  Having mulch present is not adequate when trying to attract these type of native bees.  Areas that were recently weeded are a favorite for these bees.

Approximately 1200 species of bees are considered tunnel nesting bees.  They find abandoned tunnels in debris such as dead trees, stumps, and posts.  Before removing things such as stumps and old posts, consider that they can provide a nesting area for native bees.  If you do not have any stumps or post but want to help support native bees, bee blocks are a great way to provide bees with habitat in your lawn space.  These bee blocks are simply wooden block with holes drilled into them, providing a tunnel for mason and leafcutter bees a place to live and raise their offspring.  Most commonly a simple block with holes 3/32''-3/8'' holes drilled 3''-5'' deep into it will suffice.  It's important to make sure if you are building one yourself to use a sharp drill bit in order to ensure that the holes that are drilled are smooth on the inside.  A tunnel with jagged and rough walls will often be passed up by the bees.  Make sure the blocks are on a study surface or are secured wherever they are hung up.  If the nest moves too much in the wind, the bees may leave the nesting site.  There are many ways to be creative when creating these nesting blocks.

Along with the nesting blocks, bundles of hollow plant stems can be used as nesting sites for native bees.  Things such as old bamboo stakes can be bundled together and hung from a tree to bring in some species of native bees.  In some cases using bundles of straws even works for bees.  These bundles of hollow tubes should be only a few inches long and tightly packed together.  they can be simply tied tightly together or put into a container, anything that holds the stems secure works, like old coffee cans. When mounting these stem
bundles its important to ensure the bundle is secured, if it moves to much in a wind the bees may pass up the nest.

Bumble bees are different when it comes to how they nest.  Bumble bees being social insects need a place with a little more room than the solitary, ground dwelling bees.  Bumble bees are much less choosy when it comes to finding nesting sites.  Spring queens are looking for essentially three things when looking for a nest each year.  A place that is warm, dry and roughly the size of a shoebox.  These ideal habitats can be created by creating areas with tall grasses growing dense.  Bumble bee queens often make nests in abandoned mouse nests, creating a habitat for rodents can in turn make habitat for bumble bees.  Artificial boxes can be created as well, a large wooden box with ventilation holes, soft bedding material, and a long tube for an entrance can serve as a bumble bee habitat.  If you are planning on making one, it is important to place the box in early spring in an area away from many people.  Bumble bees are gentle insects while foraging but can be defensive of their nests.

Butterflies and moths do almost all of their growing while they are caterpillars.  It is during this stage they eat almost constantly and live on the plant that they were hatched on.  Many butterflies are very particular on the plant they choose to lay their eggs on, by understanding what species of butterflies and moths choose to lay their eggs on, one can have a huge impact on butterfly and moth populations.  Perhaps the most common example of this is planting milkweed in gardens and lawns to entice visitation from monarch butterflies, since milkweed is the what makes up the entire diet of monarch larvae.  There are plenty of resources to search by butterfly species to see what larval host plant they use.  When it comes to larval plants its important to remember there is almost an unlimited amount of plants that are used by these insects.  Grasses, trees and shrubs all have species that rely on them.