NATIVE BEEZ!

Out of the approximately 20,000 bee species worldwide, about 4,000 are native to the United States. Nevertheless, non-native European bees are the most important crop pollinators in the US. Native bees are becoming more important as the number of managed bee hives decreases and the crop acreage increases.
Native bees offer a free pollination service and are very good at their job. About three billion dollars annually of crop production can be attributed to the pollination work of native bees. They are also more effective pollinators than honey bees. For example, 250 blue orchard bees (native) can pollinate an acre of apples. It would take 1-2 honeybee hives, each with 15,000 to 20,000 individuals, to pollinate this same acre of apples. Native bees are also heartier, with a greater tolerance for cold and wet weather than managed hives. Native bees are also efficient crop pollinators because of crop specialization (which I will talk about in greater detail at the end of this post because it is my FAVORITE thing about native bees) and buzz pollination. Bumblebees are particularly good at getting pollen from flower anthers because of buzz pollination, where they vigorously vibrate their flight muscles to shake the pollen out of the flower anthers. Buzz pollination is especially important for some plants, such as blueberries, cranberries, tomatoes, and bell peppers, which all have pollen released from pores in the anthers (like salt from a salt shaker) and require the help of buzz pollination to fertilize.
Now for some basic native bee biology: native bees come in many sizes, from the tiny sweat bees (< ¼ inch) to bumblebees (> 1 inch). The also vary greatly in color – they can be black and yellow, brown, solid black, or even metallic green and blue. Over 70% of native bees excavate and live in underground nests. Most do not sting – in case you needed yet another reason that we should be friends with the natives.
Now for the coolest native bee stunt: plant-specific pollination. Native bees often forage for particular flowers, often squash, berries, and orchids. These plants, when pollinated by native bees, experience increased efficiency in pollination as well as larger and more abundant fruit. Now I know who to thank for my favorite alpine Maine blueberries!
The pollination of the vanilla plant is an interesting case study of native bee pollination, namely because humans are the primary pollinators of vanilla today. Vanilla is a variety of orchid. A healthy vine produces 50-100 beans per year. It takes 5-6 weeks for fruit to develop and 9 moths for the bean to mature – basically, the growing process is intensive and necessitates constant monitoring. There is only one insect capable of pollinating the vanilla blossom – the Melipona, a bee native only to Mexico. Without pollination, the blossom wilts and falls to the ground, which means no vanilla bean grows (duh). So, when the vast majority of vanilla growing moved from Mexico, home of the Melipona, to Madagascar, not home of the Melipona, humans started pollinating each vanilla blossom by hand. This is done with a twig (or, I don’t know, a Q-tip?) to lift the flap so the overhanging anther can tough the stigma to self-pollinate. Obviously, this is a labor-intensive and inefficient process. Growers can only pollinate 5 or 6 flowers form the 20 growing on one stem at one time in order to avoid disease and ensure that the beans mature at the same time. Oh, how life would be easier for the vanilla growers if the Melipona lived in Madagascar!
Check out nativebee.html for more information (this is also the source for this blog post).