Up to a dozen tiny black wasps (Hemadas nubilipennis) will emerge from this gall in the spring, around the time when blueberry bushes are flowering. After mating, the female wasp lays her eggs under the surface of the blueberry stems. Once she has completed her egg-laying, she climbs to the tip of the shoot and repeatedly stabs it, preventing further growth.
The plant reacts to the wasp’s egg-laying by forming a kidney-shaped gall. The majority of galls (up to 70%) are formed on stems within the leaf litter. These galls can be up to an inch in diameter, and they contain many developing larvae that feed on the walls of the gall and grow during the summer, overwinter as larvae, pupate inside the gall in the spring, and then emerge as adults when the blueberry bushes are in bloom in late May and early June. The adults are almost entirely females.
If a blueberry bush has many galls, it can be problematic. A branch possessing a blueberry stem gall will not produce flower buds, and no flowers means no blueberries.
In eastern North America, the Pine Tube Moth’s primary host is the Eastern White Pine. The moths deposit their eggs on White Pine needles in the spring. The larvae hatch and use silk to form a hollow tube by binding together 5 – 20 needles. They then move up and down their silk-lined tube to feed on the tips of the bound needles. When the tube walls (needles) have been eaten down to one inch, partially developed larvae will abandon their tubes and begin constructing new ones. When feeding and development is completed, larvae pupate inside the needle tubes. There are two generations per year, with second generation pupae spending the winter inside needle tubes and emerging as adult moths in early to mid-April. Pine Tube Moths are not considered a significant pest.
Rosy Maple Moths (Dryocampa rubicunda) are easy to recognize, with their pink and yellow woolly bodies, pink legs and pink antennae. Many adults are emerging from their pupal cases now, having spent the winter underground as pupae. Once metamorphosis is complete, the adult moths lose no time in finding mates and laying eggs, not stopping to even eat. These members of the family Saturniidae are most active during the first third of the night, reducing their body temperature and activity in the morning and afternoon.
Mating takes place at night on the underside of a leaf, and 24 hours later the female lays clusters of 10-30 eggs (a total of 150 – 200 eggs) on the underside of the leaves of the larvae’s host plants, most often maples and oaks. When the eggs hatch, the larvae usually remain on the same tree throughout their larval stage.
Known as Green-striped Mapleworms, the larvae initially feed together, but become independent feeders as they age. Mapleworms change color as they develop. When young, most have black heads and yellow bodies, but with age their heads turns reddish-brown and their bodies assume a shade of green.
In New England there is only one brood per summer; further south, there are multiple broods.
June 13, 2016 | Categories: Green-striped Mapleworms, Insects, June, Larvae, Lepidoptera, Maples, Metamorphosis, Moths, Oaks, Pupae, Uncategorized | Tags: Dryocampa rubicunda, Saturniidae | 6 Comments
From the size of the chunks of sod that were ripped out of the ground in order to access this subterranean yellow jacket (Vespula sp.) nest, one can deduce that a black bear, not a striped skunk or raccoon, was the nocturnal visitor. Usually there is little intact nest left after a bear tears it apart in an effort to find yellow jacket larvae, but in this case, a portion of the paper nest remained. Apparently undaunted, even with frost in the air (signaling the demise of all the yellow jackets except young, fertilized overwintering queens), the workers lost no time in rebuilding their nest. Twenty-four hours after their nest was torn apart, the colony of yellow jackets had diligently chewed enough wood fiber to have replaced much of it.
The family Sphingidae consists of sphinx (also called hawk) moths. In their larval stage, these moths are often referred to as hornworms, because of the horn, eyespot or hardened button they all possess at the far end of their bodies. (Many gardeners are familiar with the Tobacco Hornworm (Carolina Sphinx Moth), a voracious consumer of tomato plants.)
Before overwintering as pupae, hornworm larvae feed continuously. The pictured Pandorus Sphinx (Eumorpha pandorus) feeds on both grape and Virginia creeper foliage. This particular hornworm comes in four colors – green, orange, pink or cinnamon and can grow to a length of 3 ½ inches before pupating. Each of the white spots surrounds a spiracle, or tiny hole through which air enters the hornworm’s body. A horn is present up until the last instar, or stage, of the larva’s life, at which point it is replaced by a button (see insert) that resembles an eye. The larva will soon burrow into the soil, spend the winter as a pupa, and emerge as an adult moth in the spring.(Thanks to Sadie Richards Brown for finding and caretaking this caterpillar until I could photograph it.)
September 4, 2015 | Categories: Hawk Moths, Hornworms, July, Larvae, Metamorphosis, Moths, Pupae, September, Sphinx Moths, Tobacco Hornworms, Virginia Creeper, Wild Grape | Tags: Eumorpha pandorus, Sphingidae | 2 Comments
There are many species of mud daubers — wasps that build mud cells in which they lay eggs and in which their larvae develop. The female Black and Yellow Mud Dauber gathers mud at the edge of a pond or puddle, rolls it into a ball, grasps it in her mandibles and flies it back to her nest site, a spot protected from rain, often on a man-made building. Here she constructs several mud cylindrical cells.
Like most wasps, mud daubers are predators, and they provision their mud cells with select spiders (including jumping spiders, crab spiders and orb weavers) which they locate, sting and paralyze before stuffing them into a cell. The female lays an egg amongst the spiders, so that when the egg hatches the emerging larva will have a supply of spiders (that haven’t decomposed, because they’re not dead) to eat. She seals the cell with mud, and repeats this process several times after which she covers the small group of cells with more mud. The Black and Yellow Mud Dauber larvae pupate in the fall, overwinter inside the cells and emerge as adult wasps the following spring.
July 20, 2015 | Categories: Black and Yellow Mud Dauber, Hymenoptera, Insect Eggs, Insects, July, Larvae, Metamorphosis, Mud Daubers, Predator-Prey, Predators, Pupae, Spiders, Wasps | Tags: Sceliphron caementarium | 3 Comments
Tobacco Hornworms, Manduca sexta (often found feeding on tomato plants and confused with Tomato Hornworms, Manduca quinquemaculata) are often the target of a species of a Braconid wasp (Cotesia congregata) that parasitizes beetle, moth, fly and sawfly larvae. The adult wasp lays her eggs inside the hornworm with her long ovipositor. The eggs hatch and the wasp larvae feed on the caterpillar. Eventually the wasp larvae emerge and spin silk pupa cases (cocoons) on the skin of the dying hornworm caterpillar, inside of which they transform into winged adults within four to eight days. Braconid wasps are extremely good at locating hornworms, even when there are very few to find. Because they parasitize hornworm, cabbage worm, aphid and gypsy moth larvae, Braconid wasps are considered important biological control agents. If you want to discourage Tobacco Hornworms in your tomato patch, allow the wasps to complete their metamorphosis – this accomplishes both the demise of the hornworm, as well as an increased population of Braconid wasps. (Thanks to Emily and Joe Silver for photo op.)
August 29, 2014 | Categories: Adaptations, August, Braconid Wasps, Hymenoptera, Insects, Metamorphosis, Parasites, Parasitic Wasps, Pupae, Sphinx Moths, Tobacco Hornworms | Tags: Aphids, Brachonidae, Cabbage Worm, Carolina Sphinx, Cotesia congregata, Gypsy Moth Larvae, Hawkmoth, Hornworms, Manduca sexta, Parasitoid, Pupating, Sawflies | 5 Comments