54 THE BOOK OF FORESTRY 
the wood laid on in the spring and that laid on in 
the summer, although trees like beech and maple show 
little difference. The spring wood which is laid on 
when the growing season begins and plenty of moisture 
is available consists of thinly walled elements which 
appear quite porous in such trees as chestnut and oak. 
This porous part of the annual ring gradually passes 
into the more solid summer wood where the structure 
is dense and thicker walled. 
Color.—Presence of an attractive color in wood of 
a given species may greatly increase its value, although 
many of the so-called fancy woods are highly stained. 
The presence of color in heartwood is due to resins, 
gums and oils which are usually considered by- 
products. While certain species like walnut or redwood 
have a uniform shade most others have lighter or 
darker streaks running through the colored portion. 
Most highly colored woods turn a still deeper shade 
on exposure to the air and, of course, the action of oils 
and finishing liquids in bringing out the color and 
grain is well known. While the color may appear quite 
intense, only a few woods contain dyes of marketable 
value and these are chiefly foreign; logwood and Brazil 
wood being the best known of the foreign species. 
During colonial times many colors were obtained from 
the forest for dyeing yarns and leathers, and the 
“butternut” jeans of the Confederate soldiers are well 
known. Osage orange, the roots of the barberry as well 
as the inner bark of black oak all furnish yellow dyes. 
The staghorn sumae, in addition to containing the neces- 
sary tannin for dressing leather, also supplies a dye 
which colors it yellow. The gathering of leaves and 
stems of this shrub constitutes quite an industry in cer- 
tain parts of the South. Red gum supplies a purple dye 
