Skywatch Friday: Gypsy Sky

A Gypsy Moth Caterpillar hangs from a branch by a silk thread

While the caterpillars are still small, their fastest mode of travel is to hang from a branch suspended by a fine silk thread and wait for the wind to carry it away.


My previous post garnered some very nice comments and raised some very good questions.

Jack and Joann asked if we have Japanese beetles. Yes, they do create a problem with ornamentals and grapes but no significant damage is done to other indigenous species.

Abe raised the question as to whether man had something to do with the problem. Yes, the Gypsy Moth is an alien invasive species brought to the east coast by a profit seeking businessman in the 1800’s. The only profit to be made from them is by those involved in making, distributing, and spraying pesticides. Since they have no significant natural enemies outbreaks are extremely damaging, particularly to our native oaks.

Fishing Guy mentioned that he hopes the spray doesn’t hurt the birds. The insecticide of choice is Bacillus thuringiensis or BT for short. BT is a bacterium that is fatal to caterpillars. No effect has been documented on any bird, fish, or animal species.

For more Sky Watch, vist Tom at Wiggers World

Waging War: Gypsy Moth Control

Raining death and destruction on the ravenous Gypsy Moth caterpillar; a helicopter sprays a precise pattern on the unsuspecting critters.

Spray operations are now underway using both helicopters and fixed wing aircraft. Spraying began shortly after the caterpillar hatch in early May but was brought to a standstill by the heavy rains that visited our area for the best part of two weeks. With clear blue skies the spray craft are trying to make up for lost time.

War is also being waged by another bird. Pictured here is a Gray Catbird doing its duty reducing the Gypsy Moth population.

The Plague Returns

The Gypsy Moth Caterpillars began hatching in great numbers around the first of May. As you can see in this photograph they have already riddled the new leaves on the oak trees in the affected areas.

Last year we experienced total defoliation of thousands of acres in our area and this year promises to be much worse. State and private spraying programs, although effective can only control the caterpillars on small areas of forest land. The cost to attempt to eradicate this pest would totally overwhelm state and local government if any such attempt were made.

I will once again post photos of the devastation to our forest as the season progresses. The worst will occur in late June just before the caterpillars metamorphous into adult moths. This will be the second year for the outbreak. Oaks can typically stand two to three defoliations before it proves fatal but last year was particularly stressful as we were in the midst of a prolonged drought. This spring has been exceptionally wet so for the tree’s sake I am hoping for the rains to continue.

If you are not familiar with the Gypsy Moth and their devastation, click the label “Gypsy Moth” at the bottom of this post to view my photos from last year’s outbreak.

Gypsy Moths, The Conclusion

The Gypsy Moths are finishing their life cycle. The caterpillars are gone, having metamorphosed into adult moths. I captured this male while he was resting.

A female depositing her eggs

Many females busily laying eggs are visible in this photograph. Near the bottom a male searching for a mate can be seen. With the large number of egg cases being deposited the outlook for next year appears bleak.

Gypsy Update

The carnage of the Gypsy Moths continues unabated. As the caterpillars near the end of the feeding cycle they are consuming every last piece of greenery available. In some areas hundreds of acres have been defoliated while other nearby areas are nearly untouched.

In areas of large infestations the devastation is complete and the caterpillars are on the move. In this photo one can observe the stain on the asphalt were untold numbers of caterpillars have been crushed by passing automobiles.

The Invasive Gypsies

The forests of south-central Pennsylvania are rapidly changing from lush green to somber browns and grays. As we approach summer the foliage is disappearing at an alarming rate

A closer look discloses branches as barren as in winter

The culprit is the Gypsy Moth, or rather untold millions of them

A Gypsy Moth egg case, promises more problems in the coming year


The Gypsy Moth was brought to America in the 1800’s by a French scientist who was attempting to cross them with the silk worm to develop an American silk trade. Sadly he did not know that his cross breeding was bound for failure. Whereas the silkworm spins a cocoon, the gypsy moth undergoes metamorphous in a chrysalis. A few of his worms escaped. Soon the scourge of the gypsy moth began.

DDT was used in an attempt to wipe out this forest pest but even this powerful insecticide was only able to control their numbers and slow the spread. The ban on DDT removed the most effective weapon from the gypsy moth control arsenal. Currently spraying with BT (bacillus thuringiensis) only serves to moderately slow their advance.

Our first outbreak of gypsy moths occurred in the mid 1980’s. After a few years of nearly complete defoliation the majority of our oak forest died. This in turn allowed sunlight to penetrate to the forest floor. New growth rapidly appeared and soon the new brush was providing great food and habitat for our whitetail deer. The brush in many places was so thick as to make hunting the deer difficult. With the ideal habitat the deer population exploded. A few years later when the new trees became pole timber they no longer provided the food required of the vast deer herd. The deer then focused upon farm fields. A very difficult period for farmers ensued where the deer devoured their crops leaving little if anything for the farmer to sustain his way of life. Finally early this century the Game Commission responded with increased seasons and bag limits. This combined with a couple of hard winters along with possibly other unknown factors caused the deer population crashed.

I must wonder if the return of the gypsy moth will cause this cycle repeat.