May 24, 2011 – Busy As Little Bees
QUESTION:
I am looking at a bee that appears to be a small bumblebee that bores holes in the ground the size of a pencil. What type of bee is this and what is the best control measure?
ANSWER:
The good news is that there probably is no reason whatsoever to kill these industrious little bees, because they are highly beneficial with their pollinating and pose virtually no stinging threat to anyone around them. The bad news is it may be difficult to educate your customers such that they accept this. Not all bugs need to be killed, and the garden is generally better off with many bugs than with none.
There are a number of solitary bees and wasps that burrow in the soil, and by solitary we mean they are not social wasps, have no "colony" of other workers and queen, and have no aggressive instincts toward people or pets that get near them or that opening in the soil. The only way they would sting would be in direct self defense if they were trapped in a hand or clothing. Bees that do this excavating in soil include Mining Bees (Andrenidae), Digger and Cuckoo Bees (Anthophoridae), Sweat or Alkali Bees (Halictidae), and Leafcutting and Mason Bees (Megachilidae). The female digs a vertical tunnel down in the soil and then small side tunnels off the main one. At the end of each side tunnel she creates a small cavity that she supplies with pollen and an egg, so she is providing food for her offspring but at that point she is done, and she no longer tends them. The larvae develop independently and will emerge in the summer as adult bees that go about their business of gathering pollen for the next generation.
Several kinds of wasps behave in a similar manner except they provide a cache of a paralyzed insect for their larvae instead of pollen, so these are also highly beneficial and highly unlikely to sting. The most fearsome of these is the huge Cicada Killer, which terrifies people but for very little reason. The benefits of these bees and wasps greatly outweighs any health concerns and they really should not be killed.
If the customer absolutely, positively DEMANDS that you do something your only pesticide recourse would be to treat each hole directly, and a contact dust product might be best. Dust into it carefully and then plug the hole to keep the bee in long enough to contact the dust, and late afternoon might ensure the bee is down there. You can also keep the soil so dry that the bee cannot dig a tunnel without the walls collapsing, and in sandy soils this works well. You could cover the selected soil area with something such as plastic sheeting for a temporary and seasonal fix, or bark or gravel or crushed rock for a permanent fix.
But to be really honest, if these bees were working in my own backyard I'd be thrilled, and would just sit and enjoy the show. They benefit the garden and really need to be preserved if at all possible. Hopefully some education and enlightenment will convince the customer of this as well.
View past Ask Mr. Pest Control questions.
I am looking at a bee that appears to be a small bumblebee that bores holes in the ground the size of a pencil. What type of bee is this and what is the best control measure?
ANSWER:
The good news is that there probably is no reason whatsoever to kill these industrious little bees, because they are highly beneficial with their pollinating and pose virtually no stinging threat to anyone around them. The bad news is it may be difficult to educate your customers such that they accept this. Not all bugs need to be killed, and the garden is generally better off with many bugs than with none.
There are a number of solitary bees and wasps that burrow in the soil, and by solitary we mean they are not social wasps, have no "colony" of other workers and queen, and have no aggressive instincts toward people or pets that get near them or that opening in the soil. The only way they would sting would be in direct self defense if they were trapped in a hand or clothing. Bees that do this excavating in soil include Mining Bees (Andrenidae), Digger and Cuckoo Bees (Anthophoridae), Sweat or Alkali Bees (Halictidae), and Leafcutting and Mason Bees (Megachilidae). The female digs a vertical tunnel down in the soil and then small side tunnels off the main one. At the end of each side tunnel she creates a small cavity that she supplies with pollen and an egg, so she is providing food for her offspring but at that point she is done, and she no longer tends them. The larvae develop independently and will emerge in the summer as adult bees that go about their business of gathering pollen for the next generation.
Several kinds of wasps behave in a similar manner except they provide a cache of a paralyzed insect for their larvae instead of pollen, so these are also highly beneficial and highly unlikely to sting. The most fearsome of these is the huge Cicada Killer, which terrifies people but for very little reason. The benefits of these bees and wasps greatly outweighs any health concerns and they really should not be killed.
If the customer absolutely, positively DEMANDS that you do something your only pesticide recourse would be to treat each hole directly, and a contact dust product might be best. Dust into it carefully and then plug the hole to keep the bee in long enough to contact the dust, and late afternoon might ensure the bee is down there. You can also keep the soil so dry that the bee cannot dig a tunnel without the walls collapsing, and in sandy soils this works well. You could cover the selected soil area with something such as plastic sheeting for a temporary and seasonal fix, or bark or gravel or crushed rock for a permanent fix.
But to be really honest, if these bees were working in my own backyard I'd be thrilled, and would just sit and enjoy the show. They benefit the garden and really need to be preserved if at all possible. Hopefully some education and enlightenment will convince the customer of this as well.
View past Ask Mr. Pest Control questions.
