Social woodpeckers, jolly holly berries and hot wood

Downy Woodpeckers (Picoides pubescens) can venture from their normal forest habitats in winter. Frederick County is pretty much in the middle of the Canada-to-Florida range of this common, native small woodpecker.

They are often heard or seen in winter, as they range into suburban areas and forage deeper into dead trees to find hidden insects and larva with a characteristic drum roll. How they can peck several times per second and not rattle their brains is explained by shock-absorbing cartilage between beak and skull and muscles that help pull the beak and skull apart on each stroke.

Their call is occasionally heard and resembles a metallic shriek. The 6- to 7-inch bird is black and white, with the males a little larger and displaying a red patch on the back of the head.

A social bird, the downy woodpecker will approach feeders along with other small, overwintering birds such as chickadees and nuthatches.

Jolly holly

Winterberry Holly (Ilex verticillata) is a native deciduous holly shrub. Its leaves are elongated without the characteristic spikes most think of as holly leaves. After losing its leaves in the fall, its display of red berries provides forage for native songbirds in winter. The quarter inch red berries persist into mid-winter. A plant that likes wet soils, it grows well in home gardens in moist shady areas. It attains a height of 10 to 15 feet.

Heat produced by firewood

Wood is a complex material made up of a number of organic compounds and chemicals. It's no wonder that not all firewood is created equally; some varieties are much better in producing heat, burning longer, having a pleasant aroma, not producing soot etc. Heat value of wood is usually measured in British Thermal Units. A BTU is the amount of energy required to raise the temperature of 1 pound of water 1 degree Fahrenheit.

Scientists have determined BTU values for several types of firewood, and as one might expect the denser the wood the more BTUs it puts out. Some of the top varieties for BTU output are osage orange -- 32.9 million BTU/cord, hickory -- 27.7 million BTU/cord, locust -- 26.8 million BTU/cord, apple -- 25.8 million BTU/cord and white oak -- 24 million BTU/cord.

Some of the woods on the lower end of heat output scale include lighter woods and evergreens. Evergreens have resins that initially burn hot, but their heat does not sustain very long. Evergreens also produce a lot of soot that can clog up a chimney pretty quickly, so they are not a good choice for firewood in conventional woodstoves and fireplaces.

Some woods at the lower end on the heat production scale are white pine -- 14.3 million BTU/cord, soft maple -- 18.7 million BTU/cord, basswood -- 13.5 million BTU/cord and yellow poplar -- 12.7 million BTU/cord.

For maximum energy output, the wood must be well-cured. It is estimated that green firewood has 60 percent the heat value as wood that is well cured. To get the maximum BTU output of firewood, cut trees in the winter when the sap is down, split and stack the wood, and wait one year before burning it.

Article by FCFCDB

Nature Notes for 12/13/2009