Thursday, October 30, 2008

Woolly weather.

Airborne white speck.

Yesterday, as I was retrieving pumpkin number four as part of the annual pumpkin-carving extravaganza, I noticed little white things floating around the yard, like ashes from a campfire--but they weren’t. You could coax them to land on your hand.

They were bugs – aphids. Woolly Apple Aphids (Eriosoma lanigerum)
in particular. (I am reasonably sure. Expert entomological comment is welcomed.)

Eriosoma lanigerum is found in all apple-growing areas of North America, including my yard, which contains a dwarf apple tree. It overwinters as nymphs and adults in galls on apple roots. There are four nymphal instars. The first is the most active and may disperse throughout the tree and form colonies. Adults are about 1.5 mm long, purplish, and are covered with a white, cottony wax. Adults on trees are almost invariably females, and reproduce asexually, usually viviparously. Winged adults appear in late summer and fall and during pumpkin carving season. This is the stage that disperses to other trees.

To learn more about this dust-mote creature, including its significance as an agricultural pest, see here.



A funny thing is that after seeing the first batch, I have been seeing them all day today, all over the neighbourhood—because I have been looking for them. They are likely one of those things that once you are aware of them, you realize you have probably been overlooking them all these years. Little white things, floating in the air.

2 comments:

swamp4me said...

Strange you should mention these. I had a very similar experience a few weeks ago. Floating woollies were everywhere and I didn't realize what they were until I caught one in my hand. Egads! An aphid. Odd that I had never noticed the winged ones before. Isn't it nice that life offers up these little surprises just to keep us on our toes.

Hugh said...

Yes it is. It's also nice that things change throughout the year and a year later we get to rediscover things we had forgotten about. Kids! The woolly aphids are back!