Creative Woodworks & crafts 2005-11, страница 42

Creative Woodworks & crafts 2005-11, страница 42

by Wes Demoresf

White Birch, Lietida papyri/era, aka Paper Birch, Canoe Birch

Black Birch, Be.tula lenta, aka Cherry Birch, Sweet Birch

Yellow Birch, Betula aUeghanie.nsis

Gray Birch, Betulapopidifolia, aka White Birch

Red Birch, Betula nigra, aka River Birch

The birch family (iietulaceue) is well represented in the northern hemisphere and encompasses Alder, Hornbeam, and Hazelnut, but this profile will deal with only the birch members of the family. Any field guide typically includes at least 18 different species that range from 6" dwarf to full-size beauties in the wild, with more than 30 cultivated landscaping varieties. Tn this article, I will cover only those species that have use to us as woodworkers.

Tn most cases, the names for the Birch species relate to the color of the bark, and that is their most distinctive field identification characteristic. Of the five species, American While Birch, Yellow Birch, and to a lesser extent, Black Birch, it re commercially harvested to supply the needs of the lumber and veneer trade. Red Birch and Gray Birch do not attain sufficient size for commercial harvesting, but they are useful as firewood, pulp wood, and craft wood.

American White Birch has the widest distribution, growing across Canada, Alaska, and parts of the northern United States. Yellow Birch has a smaller range, from lower southeastern Canada and northeastern United States and south throughout the Blue Ridge Mountains to Georgia. Black Birch is hardly found in Canada and grows in a narrow band from southern Maine down to northern Georgia aixl Alabama. Each has its preferences for soil, climate, and topographic conditions.

White Birch is intolerant of shade, as are most pioneer species. (Pioneer species are those that are the fiTst to grow in cut over, burned over, or storm damaged areas and begin a new forest succession.) Once competiti ve species gain dominance, the White Birch die off, or at best, cease to grow. However, there can be stands comprised exclusively of birch, with other White Birch being the only competition. In a good stand, they can attain heights of 70' and diameters over 20". with outstand-1

White Birch tree

S ffcv

X'vKv

A V y» < ^

I'Tf. /.g

■ft .

SvA^'-y-,.:

m i ■ • >

■ ■/ ■ " -

iJ.. | ■

■fy ••»

"> A..' ViO • > fA".

■ v. ; '

1 « " ;

Birch

ing specimens reaching over 100' tall and 6' in diameter. This is a short-lived species, with specimens seldom living more than 140 years, although some have managed to survive more than 200 years. Because of this, and the face that it reseeds heavily. White Birch can be managed for faster turnaround to market than most other hardwood species.

Black Birch is also intolerant of shade and has pretty much replaced American Chestnut in stands where the latter once grew, ll have watched the succession of these | trees on my own property. On pasture fields that we had let go fallow, Black and Gray Birch seedlings soon covered the ground. However, after 50 years, only a few spindly Black Birch are alive, and every spring we find a few more that cannot stand the succession of Hickory, Oak, and Maple. In certain locations though, where the soil and topographic conditions are more favorable to birch, they can grow to 70' tall with diameters tip to 3' in diameter and yield beautiful lumber. This tree is a longer-lived species, and some specimens can be found in excess of 2001 years old.

* •

-J

A - *

1

"I

i ■ \ V % ;;•■ t

I

F*

" \ J t' j'

; W*

f r

Ti v

. ■ >

YeJIow Birch tree

Black Birch tree

Yellow Birch is more tolerant of shade than the other species and can be found growing in mixed stands where ji is slow growing and long lived. Like Black Birch, it produces beau-til'ul lumber. Tt prefers cool temperatures and abundant precipitation, but it is widely tolerant of varying soil and topographic conditions. Tt typically grows to heights up to 100' with diameters greater than 30". In good stands, it can grow to a little over 100' tall with diameters at breast height (DBH) over 4', and it can live well over 300 years.

42 • Creative Woodworks fi Crafts November £005