DEAR SUN SPOTS: Those ugly cocoon-like nests are back in many trees. There seem to be more each year. I don’t know what bug makes them. Some trees are completely covered.

I got rid of a nest a few years ago by cutting it with loppers. I put it in a garbage bag, sprayed it with WD-40 and took it to the transfer station. The bush is still there and healthy.

I wonder if there is another recommended way of getting rid of them. It would certainly be nice if every town made a concerted effort to do away with as many as possible.

Landowners can get rid of the ones they can easily reach. — Nancy, Bryant Pond

ANSWER: Sun Spots cannot be sure which moth makes the nests you are referring to, but she will address the moth that poses the biggest threat, the browntail moths described on the www.maine.gov website.

At http://tinyurl.com/2avosa4 you can read about the history of these moths, which were introduced to Massachusetts from Europe in 1897.

The site says that “while feeding damage may cause some concern, the primary human impact from the browntail moth is the result of contact with poisonous hairs found on the caterpillars. Contact of these hairs with human skin causes a rash similar to poison ivy that can be severe on some individuals.”

It also says that “pupal cocoons are full of toxic hairs and should be removed from buildings or trees only with great caution.”

The moth is described as having “a wingspread of about 1 1/2 inches. Wings and midsection are pure white. The abdomen (rear part of the body) is brown with a conspicuous tuft of brown hairs at the tip.”

There are other moths that build nests in trees: “Fall webworm nests, often confused with the browntail moth winter webs, are loose, further in on the branches and more often found in ash trees then oak or apple. Eastern tent caterpillar tents are found in crotches and forks of apple and cherry tree branches during the spring.”

The caterpillars also look different. The larvae of the browntail are “about 1 1/2 inches long, are dark brown and have a broken white stripe on each side of the body and conspicuous, unpaired, reddish spots on the posterior end of the back. These should not be confused with larvae of the eastern tent caterpillar which has a single, solid, white stripe down its back or the gypsy moth which has paired blue and red spots on its back.”

Although it appears that the damage to trees is not a huge issue, because of the reaction they cause in people, the site does recommend some methods to control browntail moths.

“Non-chemical: Control of browntail moth populations in isolated areas may be obtained by clipping the overwintering webs and destroying these webs by either soaking in water and detergent or burning them. This control should be undertaken in the winter and very early spring — September to mid-April.

“Chemical: Undertake control measures as early as possible to reduce the exposure to the irritating caterpillar hairs. Pesticides should be applied when caterpillars are present and feeding, from early May through the end of June. Webs and larvae that are high up in trees are difficult for a home owner to effectively control, seek professional help from an arborist who is a licensed pesticide applicator Note: There are special regulations regarding control of browntail larvae within 250 feet of marine waters. A licensed pesticide applicator should perform control work in these areas.

“In other locations where larvae are within reach, Pyrenone or Sevin (these chemicals are not allowed within 250 feet of marine waters) should provide acceptable control results. Only registered fruit tree formulations should be used on apple and other fruit trees.”

Please be careful in the use of Sevin. It is deadly to bees and other beneficial insects and totally banned from Sun Spots’ garden.

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