People Are Debating Exactly What This is in Maine, New Hampshire Trees
Odds are no matter where you are, be it Maine or New Hampshire, and matter where in those states you are, you've seen these pop up on trees and bushes in your neighborhood or in other areas.
But what exactly is it? It essentially looks like a transparent spiderweb covering portions of trees and/or bushes, also looks like a crystal forcefield surrounding certain branches and leaves. After noticing this silky wonder on a tree in her yard, Kathleen LeJeune did what the rest of us do when we have a question -- ask our peers and strangers on Facebook (via the u Local New Hampshire Facebook page).
Right off the bat, one of the first comments attempting to answer Kathleen's question came from a man named Kenny L'Abbe in Keene, New Hampshire, who believed it was made by the gypsy moth. Kenny's guess makes sense, as gypsy moths have been known to spin web-like structures while in caterpillar form before retreating into their cocoons to later emerge as a moth, as seen in this picture.
However, when comparing the picture with the link above to Kathleen's picture, there are two major differences: 1) In Kathleen's picture, the web-like structure is more transparent and almost comes across as a big, thick icicle as opposed to a thick white web, 2) The gypsy moth caterpillar cocoons are visible all over the web-like structure in the picture provided at the link, whereas Kathleen's picture shows none. So, the gypsy moth can more than likely be ruled out.
The Fall Webworm
Another suggestion, from a woman named Dottie McDonnell, was the fall webworm. As seen in this picture, the fall webworm's web-like structure does seem to be a bit more like the one in Kathleen's picture, as far as a bit more transparency and crystal-like features go; however, much like the gypsy moth, the cocoon's of the fall webworm can be seen in the accompanying picture, unlike in Kathleen's.
Plus, according to the University of Florida's Entomology & Nematology Department, the fall webworm can basically cause complete defoliation of trees and shrubs. And the area that's encapsulated in the crystal-like structure in Kathleen's picture seems to still have leaves and whatever fruit is hanging from that tree inside, which contradicts the fall webworm's behavior. However, because the silken nest still looks similar, it can't completely ruled out.
Eastern Tent Caterpillar
The third and most likely option is the eastern tent caterpillar, as suggested by Laurie Wilson and others. According to the University of New Hampshire, the eastern tent caterpillar is often confused for the fall webworm. Both create very similar silken nests that appear as those web-like structures; however, while the fall webworm tends to weave their nest around branches, the eastern tent caterpillar usually weaves it in the forks of trees, which is what seems to be shown in Kathleen's picture.
On top of that, another point that's been brought up in this whole article -- both the gypsy moth and the fall webworm can be seen inside of their nests during the daytime; however, the eastern tent caterpillar doesn't feed inside their nest during the day, according to UNH, but will return to the nest at night. Considering no insect or cocoon can be seen inside of the silken nest in Kathleen's picture, it's safe to say that the eastern tent caterpillar is the right guess in this instance.
Somewhere, on a Hollywood lot that doesn't exist anymore, Gil Grissom is impressed with this full breakdown of Northern New England entomology. (Hopefully, you get that CSI: Crime Scene Investigation reference).