Question of the Week

Fall foliage season is here! According to the Virginia Department of Forestry, the trees producing this beautiful display are:

• Ash - yellow, maroon leaves
• Beech - yellow to orange leaves
• Dogwood - scarlet to purple leaves
• Hickory - golden bronze leaves
• Oak - red, brown or russet leaves
• Poplar - golden yellow leaves
• Red maple - brilliant scarlet leaves

Leaf color is nearing its peak this week in the higher elevations of southwest Virginia and along the Blue Ridge Parkway. The Shenandoah Valley is at about 50% peak and the Piedmont is at about 25% peak. The Coastal Plain will peak around mid-November.

How do you think officials predict the dates of peak fall color?
     a. cool temperatures at night
     b. freezing temperatures at night
     c. shorter days, longer nights
     d. soil moisture
     e. leaf spotters

Answer:  Believe it or not, fall foliage predictions are made by leaf spotters - park rangers, foresters, lodging and restaurant operators, chamber of commerce officials, etc. “If we’re driving somewhere, we’re looking,” says one official. Leaf spotters send fall foliage reports to the state tourism division or visitor's bureau who then post it on a website. Many states also have a hotline and will provide text alerts.

In Virginia, go to the Virginia Department of Forestry website for the latest report on Virginia's fall foliage. If you want to avoid the crowds on Skyline Drive, the website also includes fall foliage driving tours.

http://www.dof.virginia.gov/fall/index.htm

A Webworm Horror Story

Last Sunday I decided to enjoy the beautiful fall weather and eat my lunch outside. About halfway through my sandwich, I glanced up to see something fuzzy crawling down my bangs onto my nose – UGH! It was a fall webworm – you know, those nasty hairy caterpillars whose giant webs appear on tree branches every fall? There seems to be a bumper crop this year – caterpillars are crawling on everything: across yards, along sidewalks, up walls, on decks and porches… you get the picture. When I went outside to eat, I purposely positioned my chair away from the trees to avoid them (and to avoid the occasional falling walnut – ouch!). This fellow found me anyway and sort of put me off my lunch.


Description of Damage
In the grand scheme of things, fall webworms do not do a tremendous amount of permanent damage, although the webs are definitely unsightly. Caterpillars feed on leaves inside the webs, gradually enclosing more foliage as they grow. Heavy infestations may defoliate a tree but rarely kill it. Over 100 species of trees play host to these voracious pests, but here in central Virginia, they seem to prefer nut and fruit trees, such as walnut, pecan, cherry and crabapple.

Life cycle

The adult moth is snow white, often with dark spots, and somewhat hairy (not surprising, considering the caterpillar). They lay their eggs on the underside of leaves in May through July. The larvae hatch in about 2 weeks and immediately begin to spin webs and feed on leaves. Pupation occurs after 4 to 6 weeks of spinning and feeding and can usually be found in leaf litter or just below the surface of the soil. In the South, we are especially lucky - we get at least 2 generations per year!

Control
Control is not necessary; however, you may not be able to tolerate the unsightly mess. If you do decide to take action, mechanical control is best. When you can reach them, prune branches containing webs and destroy them. Chemical control must be done when webs and larvae are small, no later than July, but it is not necessary. If you are lucky, birds and other natural predators may come to your yard and do the job for you!

Just remember – do not eat lunch under the webworm tree…

For more information, go to http://pubs.ext.vt.edu/2808/2808-1013/2808-1013.html