No. 2, September, 1920] FORESTRY 175 



1318. Dickie, F. Discovery of sugar on Douglas fir. Amor. Forestry 26: / fig. 



1920. — The Indians of British Columbia knew of the existence of sugar on the Douglas fir 

 long before the first white man came to North America. Only now the facts have been ascer- 

 tained. Reporting upon the findings of Prof. Davidson and Mr. Tejt, the writer states that 

 "fir sugar" is occasionally formed during summer droughts or in dry-belt regions, sugar-bear- 

 ing trees being most abundant between the 50th and 51st parallels and between 121°-122° 

 longitude. The "manna" is a natural exudation from the tips of the needles, occurring as 

 white masses ranging from | inch to 2 inches in diameter on leaves and branches. A slight rain 

 may quickly dissolve the sugar and it may be found recrystallized in patches at the base of 

 the tree. At other times it remains in a semifluid condition. The sugar contains nearly 50 

 per cent of the rare trisaccharide, melezitose. Sugar-producing firs are chiefly those standing 

 on gentle slopes facing east and north in compar.it ively open areas. In these situations, the 

 leaves being exposed to the sun, an abundance of carbohydrates more than normal are formed 

 during the day, which are not stored or carried to the growing tissues, as is the case with Doug- 

 las fir in heavily forested areas. The ground and atmosphere being dry, an increased root 

 pressure and cessation of transpiration cause the leaves to become water-gorged. This water 

 contains a sugar created by the reconversion of starch into sugar. By evaporation, the sugar 

 is deposited on the leaf tips. By reason of the necessity for a succession of sunshiny days to 

 produce the sugar, the Douglas fir does not yield a harvest that can annually be depended 

 upon. — Chas. H. Otis. 



1319. Dickie, F. Sugar from the Douglas fir. Sci. Amer. 122: 165, 174-175. 1 fig. 1920. 

 — The sugar-yielding firs are confined to the dry belt of British Columbia, and are chiefly 

 found in the hottest parts of the interior of the province between parallels 50° and 51° and 121°- 

 122° longitude. Trees standing on gentle slopes facing north and east and which are fairly 

 wide spaced produce sugar in greatest abundance. The sugar occurs in white masses scattered 

 over the foliage and branchlets, the accumulation of drops; drops of small size may appear 

 upon the leaves at the tips and sometimes two or three tips will become imbedded in a very 

 large drop. Analysis shows that the sugar yields about 50 per cent of the rare trisaccharide, 

 known as melezitose. The Indians of the region have known of this occurrence of sugar on 

 the Douglas fir for a long time and gathered it whenever available; but it is an uncertain 

 crop, owing to reasons of climate. — Chas. H. Otis. 



1320. Drolet, George. Turpentine orcharding effect on longleaf timber. Jour. Forestry 

 17 : 832-834. 1919. — Turpentining with only slight damage to virgin longleaf timber has been 

 successful in Alabama under a system where the crops are worked for only 2 years and then 

 logged. Only healthy trees over 12 inches are tapped and not more than two cups are placed 

 on a tree. Results of 4 years' work are given which show that there is a loss from turpentine 

 operations which may be kept small, and that this loss increases with the length of the opera- 

 tion. — E. N. Munns. 



1321. Dunbar, John. Forty-two distinct forms of hickories. [Rev. of: Sargent, C. S. 

 Notes on North American trees— II. Carya. Bot. Gaz. 66: 229-258. 1918.] Amer. Nut. Jour. 

 10:20-21. 1 fig. 1919. 



1322. Eldredge, I. F. Management of hardwood forests in the southern Appalachians. 

 Jour. Forestry 18: 284-291. 1920. — An outline is given of a management plan for use in the 

 hardwoods. The problem presented is one of area regulation with 6 age-classes to be consid- 

 ered in arriving at the volume of cut in any period in the working circle. — E. N. Murms. 



1323. Eysselt, Joh. "Weidwald." [Pasturewood.] Oesterreich. Foist.- u. Jagdzeitg. 

 38: 1-2. 1920. — The present high value of grazing lands is leading to a demand for the ex- 

 tension of "pasture-woods" particularly in the alpine forests. This is considered contrary 

 to public policy, however, as it would entail injury to exceedingly valuable protection forests, 

 and lead to the extension of mountain torrents, avalanches and landslides, while experience 

 as shown that the removal of the timber has also led to a deterioration of the pasturage 



