Friday, October 31, 2008

Plant Your Bulbs Now

When should we plant spring and early summer flowering bulbs? The answer is NOW to be sure they are planted in time to develop a root system and satisfy the cold requirement of the bulbs. You will want to wait until soil temperatures are below 60 F (16 C) before planting. In Henderson County, this is usually late October to November.

Where should we plant our bulbs? We need to plant in soils with good drainage. If the soil is mostly clay, mix in an organic amendment such as peat moss, compost, aged bark, etc., up to 50% in volume, or plant in raised beds. If the soil is mostly sand, add an organic amendment to increase water and nutrient holding capacity. Soil pH is critical! The pH of the planting area should be in the 6-7 range.

Spring flowering bulbs can be used in beds with annuals or perennials, borders, ground covers, rock gardens, and wooded areas. For perennialization, avoid planting them near heated basements. These bulbs do best in areas that do not receive direct sunlight during midday, especially during hot summer months.

Tuesday, October 14, 2008

Fall Color is Just Beginning, What is the Cause?

All during spring and summer the leaves have served as factories where most of the foods necessary for the trees' growth are manufactured. This food-making process takes place in the leaf in numerous cells containing the pigment chlorophyll, which gives the leaf its green color. Along with the green pigment leaves also contain yellow or orange carotenoids which, for example, give the carrot its familiar color. Most of the year these yellowish colors are masked by the greater amount of green coloring. But in the fall, partly because of changes in the period of daylight and changes in temperature, the leaves stop their food-making process. The chlorophyll breaks down,. the green color disappears, and the yellowish colors become visible and give the leaves part of their fall splendor.

At the same time other chemical changes may occur and cause the formation of additional pigments that vary from yellow to red to blue. Some of them give rise to the reddish and purplish fall colors of leaves of trees such as dogwoods and sumacs. Others give the sugar maple its brilliant orange or fiery red and yellow. The autumn foliage of some trees, such as quaking aspen, birch, and hickory, shows only yellow colors. Many oaks and others are mostly brownish, while beech turns golden bronze. These colors are due to the mixing of varying amounts of the chlorophyll and other pigments in the leaf during the fall season.

Fall weather conditions favoring formation of brilliant red autumn color are warm sunny days followed by cool, nights with temperatures below 45o F. Much sugar is made in the leaves during the daytime, but cool nights prevent movement of, sugar from the leaves. From the sugars trapped in the leaves the red pigment called anthocyanin is formed. The degree of color may vary from tree to tree. For example, leaves directly exposed to the sun may turn red, while those on the shady side of the same tree or on other trees in the shade may be yellow. The foliage of some tree species just turns dull brown from death and decay and never shows bright colors.

Through fallen leaves, Nature has provided for a fertile forest floor. Fallen leaves contain relatively large amounts of valuable elements, particularly calcium and potassium, which were originally a part of the soil. Decomposition of the leaves enriches the top layers of the soil by returning part of the elements borrowed by the tree and at the same time provides for more water-absorbing humus.

North Carolina leads the parade for leaf lookers, and depending upon the season, the species of trees involved, and the relative proportion of the three pigments, just about every imaginable color combination may be seen.

Prepared by Dr. Robert Bardon Extension Specialist

Tuesday, October 7, 2008

Cool Weather Brings Insect Pests

Cooler weather is welcomed by most of us but what isn't welcomed is the accompanying increase in activity by some insects.

The "Polistes" or paper wasp colonies are beginning to wind down their activity, particularly in western NC. Some of the remaining workers (who will die in the next few weeks) along along with next year's crop of queens are bailing out of their summer nests. Neither pesticides nor the downturn in the housing market appears to deter these once and future queens from finding affordable housing.

We are getting calls from people who see the wasps outdoors hovering about the eaves, soffits, and porches, particularly on warm fall days. For whatever reason, the wasps seem to orient
to vertical objects so chimneys become an object of their attention. Same is true for cell phone towers, water towers and other such objects.

At some point, the wasps make their way indoors and things can get more exciting. You often see/hear the wasps moving about slowly and bouncing off windows, ceilings, light fixtures, etc.

Trips to the attic can be adventures as people often spot multitudes of the wasps buzzing about. Cold weather stops the activity, but quite likely on subsequent warm winter days you will find wasps flying about indoors or again spot them outside around the roof area.
Here are a few tips to remember:
First - seeing the wasps does not mean that there is a nest in a wall. More likely there is a nest outdoors nearby.
Second - since these are mostly queens looking for overwintering sites and not workers defending an active nest, they are not aggressive and so stinging incidents are rare.
Third - spraying indoors is an exercise in futility because there simply isn't a specific target area you can (or need to) treat.

When does it stop? Your guess is as good as mine. We're not into any real cold weather yet. As I said earlier, you can expect it even after periods of cold weather seems to have brought it to a halt, but when the outside air temperature (and sun heating walls of homes) is adequate for activity to occur you will see a them.

Best advice:
First - Keep a rolled-up newspaper handy. Yes, you can unload an entire can of "Raid" on the beast but then what do you do about its 'sisters' that are likely to show up?

Even that preferred weapon of choice for many homeowners - setting off foggers in every room - won't accomplish much either because any wasps that are not out in the open at that time will not be affected by the chemical mist.

For further information about paper wasps, check out:

Mike Waldvogel, NCSU Entomolgy