Gardeners, naturalists, researchers, conservationists, politicians — everybody talks about pollinators these days. It seems that pollinators need our help and we need to help them help us. However, it is really hard to protect something that we don’t fully know. So let’s take a look at our insect pollinators, how and when to look for them, and how to tell them apart.
Bees are one of the most important groups of pollinators. Aside from the well-known non-native honeybee, bees are very diverse in terms of size, ecology, and coloration. In our area, bees range from very small (like our metallic sweat bees) to large (like our carpenter bees and bumblebees), and display different colors and even metallic shines. Bees can be recognized because they have two pairs of wings, ‘elbowed’ antennae, and usually hairy legs and bodies. Bees fly and visit flowers both during daytime and dawn, and can be seen on flowers of different colors (e.g., pink, purple, blue, white, yellow).
Butterflies have ‘conflictual’ relationships with their preferred plants: while in their caterpillar stage they feed on the leaves and stems, they pollinate flowers in their adult butterfly stage. Maryland butterflies span different sizes, colors, and shapes. You may be familiar with the impressive Monarchs, who feed on milkweed and are able to migrate hundreds of miles, our very own state insect the rare Baltimore Checkerspot, or the beautiful swallowtails. Because of their special mouth shape with a rolled ‘tongue’, butterflies prefer flowers that have long tubes. Butterflies are diurnal and are usually attracted to red, orange, yellow, purple and mauve flowers.
Moths are relatives of butterflies, but from a pollination perspective, they differ because the majority of them are active at dusk and into the night. Like butterflies, moths have long tongues that they use to collect nectar from flowers, and thus their preferred flowers are somewhat tubular. Moths can be small or large, but the vast majority of them are attracted to flowers that bloom in the evening, produce strong and sweet scents, and are usually whitish. While some pollinating moths are fair fliers, the impressive hawkmoths can hover and are easy to recognize because they are very hairy and fly like hummingbirds. Even though most moths are nocturnal (active at night), some hawkmoths are diurnal (active during the day), such as hummingbird moths.
I hope that after reading this, you will appreciate these little guys as much as I do. Despite hoverflies contributing to a VERY large part of the pollination of both crops and wild plants, they are unfairly overseen, so let’s set the record straight! Hoverflies are relatively small (about half-an-inch). They are flies and thus have only one pair of wings that they carry openly as a ‘T’. Hoverflies often are confused with bees and wasps because many of them have yellow stripes on their abdomens. However, it is relatively easy to tell them apart because they have two wings (versus four in wasps and bees), they hover and make very fast movements when they fly, they usually have huge eyes, and their antennae are very short. Hoverflies are diurnal pollinators and prefer white, yellow and greenish flowers.
Certain families of this very large group of insects visit and pollinate flowers while feeding on pollen. Beetles that pollinate can be minute to large. One can recognize them because of the hard ‘shield’ that covers their backs and the usual hair that covers at least part of their bodies. Beetles can be active during the day and night hours and prefer flowers that are greenish, white and relatively dull. In Maryland, most of our pollinator beetles are soldier and longhorn beetles. Next time you are around flowers, I invite you to take a close look and I am sure you will have no trouble finding these guys!
This is definitely a pollinator but I still don’t know what it is!
Have you found an insect on your flowers, but you can’t figure out what it is? There is a great tool to identify it, and it is just one picture away! This magical tool is a phone app called iNaturalist. After taking a picture of the insect in question you can upload it to the app and submit it for identification. This app will let you know what is likely to be the species you have seen. It also will let other users like you learn from your observations and help you identify them. Also, besides letting you visually search for observations close to you, the app/website is simple to use, and the users are friendly and helpful. To learn how to use this app/website, refer to this very good tutorial on iNaturalist.
By Anahí Espíndola, Assistant Professor, Department of Entomology, University of Maryland, College Park
Many of our natives are pollinated by ants, which can be more reliable out in desert regions. Bat pollinated plants are nocturnal, like some flowers who are pollinated by nocturnal moths. They tend to smell fruity and sweet. Some exotic plants in the arum family are pollinated by flies, so consequently smell like . . . what flies like. It is all so fascinating. I just commented to someone a moment ago about how so many trendy pollinator flowers, as well as the all too common blue gum eucalyptus, distract pollinators from the native plants that rely on them in the wild.
Pollination is so diverse, and it can involve so many types of different organisms! Ants, beetles, wasps, little rodents, bats, flies… they all fall for the sweet rewards that plants have to offer, even if sometimes they get lured and ‘exploited’ by the plants while doing so… like in those Arum species you talked about where the pollinators are sometimes trapped by the plant until the flower can ‘finish using them’ for their pollination, or in many Orchids that actually lure males of some wasp species by looking like their females.
Pollination is really all around us, and it comes in so many different forms that it is really fascinating! It is now a regular activity of mine to actually stop at whatever flower I see and check if somebody’s in there. I am never disappointed, and always amazed by what I find!
Mature date palms became trendy in the early 1990s, because they were less expensive than the Canary Island date palms. They were being recycled from the orchards around Las Vegas as more spaces for all the development that was happening back then. Productive trees that are desirable in orchards would have been messy in landscapes. To avoid the mess, only the female trees were recycled! Without the male stud trees, there were no messy dates.
This was a great article and we learned a lot. We have some questions! How do wasps fit into the picture? My son is 4 and in Wild Kratts learned about the invasive species of the longhorned beetle from China… Is there a native version of beetle that pollinates in Maryland or is our most common pollinating beetle invasive? Thanks! Pictures appreciated!
Wasps can also contribute to pollination. The vast majority of wasps are carnivorous and thus visit flowers to complement their diets with more sugar (from nectar) and sometimes just for water (also from nectar). Because the diet of most wasps is not based primarily on nectar, most of them (there are a handful of exceptions) don’t have many adaptations for collecting nectar (e.g., long tongues) or pollen (they are hairless). However, because they do visit flowers for nectar they contribute to the pollination of those flowers. Again, because they are not adapted for collecting pollen and nectar, they usually visit flowers that have those rewards easily accessible, and thus it will be rare to see them visiting tubular or narrow flowers.
Now, as I mentioned in another reply, some plant exploit wasps to get pollinated, but without giving any reward in exchange (they are cheaters!). Some Orchids lure males of certain wasps by looking like the females of those wasp species. The male is attracted to the flower, and ‘thinking’ that it is a female of his species, they try to mate with it. When doing so, they actually pollinate the flower!
Another fun story related to wasps that pollinate is that of fig-wasps. These are tiny wasps that are specialized in pollinating fig trees. I can write another blog about those ones, because they are super fascinating and deserve all the attention, but to learn more for now you can take a look at this page (https://www.fs.fed.us/wildflowers/pollinators/pollinator-of-the-month/fig_wasp.shtml).
I love Wild Kratts! There are indeed many long horned (and other) beetles that are native to Maryland and that contribute to pollination of native flowers, so that means that the most common pollinating long horned beetle is likely not the invasive one. There are some examples of such beetles in the blog, but if you would like to know about some other ones, feel free to scroll this inaturalist page (https://www.inaturalist.org/observations?place_id=39&subview=grid&taxon_id=47961), where you will find many of them!
Also, you can learn more about other invasive species from Maryland here (https://extension.umd.edu/resources/yard-garden/invasive-species/invasive-insects).