HORTICULTURE, 443 



The varieties of olives growing in the nonirrigated plantations described 

 were of European origin and accustomed to abundant moisture. In view of 

 the remarkable drought resistance of these varieties, the author concludes that 

 by the use of the desert variety Chemlali, together with the adaptation to our 

 conditions of the Tunisian methods of planting and culture, large areas of 

 land in the Southwestern States, possessing a suitable soil and climate, but 

 now undeveloped from lack of irrigation water, may be utilized to produce 

 olive oil. Trial plantations are now being made at various points in the arid 

 region to determine whether such dry-land olive culture will prove a com- 

 mercial success. 



The after effect of coinm.ercial fertilizers in vineyards, F. Gvozdenovic 

 (Ztschr. Landw. Versuchsw. Ostcrr., 13 (1010), No. 11. pp. S35-S'il). — In con- 

 tinuation of previous demonstration experiments conducted in various vineyards 

 in Gorz-Gradiska, Austria (E. S. R., 21, p. 738), data are given to show the 

 residual effect of fertilizers the year following application. 



The returns from some 43 experimental areas show an average net increase 

 in yield of 1,030 kg. (over 1 ton) of grapes per hectare on the vineyards re- 

 ceiving a complete fertilizer over the unfertilized vineyards, the value of the 

 fertilizers having been deducted. Since sufBclent quantities of stable manure 

 are difficult to secure, it is recommended that as a general thing the vineyards 

 be rather heavily manured at least every 5 years and that every second year a 

 moderate quantity of commercial fertilizer be applied. 



Experiments in blueberry culture, F. V. Coville {U. 8. Dept. Agr., Bur. 

 Plant Indus. Bill. 193, pp. 100, pis. 18, figs. 31). — A full account is given of the 

 author's investigations, conducted largely with swamp blueberries {Vaccinium 

 corymbosum) , and consisting primarily of extensive pot cultures and laboratory 

 studies, relative to their soil requirements and method of nutrition. From the 

 knowledge thus gained, a system of pot culture, herein fully described, has been 

 developed by the use of which seedlings of the swamp blueberry have been 

 grown into robust plants to a maximum height of 27 in. 12 months from 

 germination, at which period 70 per cent of the plants had laid down flowering 

 buds for the next spring's blossoming, whereas J. Dawson, an earlier investi- 

 gator, found that the swamp blueberry required from 4 to G years to produce 

 fruit from seed.** The growth development of the swamp blueberry seedlings, a 

 method of pollination in the absence of outside agencies, possibilities of im- 

 provement by breeding and selection, and preliminary experiments in propaga- 

 tion and field culture are also considered. 



The results of the soil investigations as a whole led to the conclusion that 

 the swamp blueberry does not thrive in soils generally favorable to the devel- 

 opment of agricultural crops, such as rich garden, heavily manured, or heavy 

 clay soils, soils made sweet by lime, or even thoroughly decomposed leaf mold 

 such as has a neutral reaction. For vigorous growth the swamp blueberry re- 

 quires an acid soil, the favored type of which is peat. The author is of the 

 opinion that peat is particularly satisfactory because the acidity of peat, al- 

 though of a mild type, is continually maintained. Although the roots of the 

 swamp blueberry may be submerged in water during a portion of the year, 

 they require a well-aerated soil in the growing season. Aeration conditions sat- 

 isfactory for the blueberry are prevalent in sandy soils, drained fibrous peat 

 land, and in masses of live, moist, but not submerged sphagnum. In the latter 

 situation the chief nourishment of the blueberry plant comes from the bog 

 water sucked up by the sphagnum and not from the sphagnum itself. The 

 failure of previous experimenters to domesticate and improve the blueberry are 



oCult. and Country Gent., 50 (1885), p. 660. 



