520 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



almost everywhere that the grape vine is found throughout the United States 

 and Canada, and since this species is not recorded as occurring in Europe, 

 it is doubtless a native of America. It was first reported from Missouri in 1825, 

 and by 1897 had become so serious a pest in California as to be placed next in 

 destructive importance to the grape Phylloxera. 



It is a sucking insect in both the nymphal and adult stages, and injures the 

 plant by inserting its thread-like proboscis in the underside of the leaf and 

 extracting the juices therefrom. The result of these punctures is a whitening 

 in patches on the upper surface of the leaf, which later turns brown, and finally 

 the leaf falls from the vine prematurely, thereby checking the development of the 

 vine and reducing the fruit crop considerably. 



Field experiments prove conclusively that this pest can be controlled by 

 spraying against the nymphs with a tobacco extract solution. — V . G. J. 



Gummosis. By G. P. Darnell-Smith {Agr. Gaz. N.S.W. vol. xxvi. pp. 405- 

 410). — The gumming of fruit trees may be due to unsuitable soil, excessive 

 moisture, or excessive manuring. It can also be caused by certain fungi, bac- 

 teria, boring insects, frost, or unequal growth between scion and stock. The 

 remedies are judicious pruning of the roots, application of lime to the soil, or in 

 the case of Peach trees apply 2 lb. of salt to each tree, slit the bark spirally and 

 remove dead bark. — S. E. W . 



Hemlock, The Eastern. By E. H. Frothingham {U.S.A. Dep. Agr., Bull. 152, 

 February 3, 1915). — In spite of its present importance, hemlock is not a tree 

 of promise for forest planting. White and red pine will yield better lumber in a 

 much shorter time and on poorer soils, are less susceptible to decay, and are 

 more easily grown. Spruce serves as well for the protection of watersheds and 

 stream sources, and produces better pulpwood and lumber. Several other 

 species produce fully as good tan bark or extract in a shorter time. Nevertheless 

 hemlock will undoubtedly persist in the old-growth forests and natural second- 

 growth in many regions, and its presence in these stands may be of decided 

 benefit to them. 



Though hemlock first came into use because of the growing scarcity and in- 

 creasing value of better trees, it can no longer be considered merely a substitute 

 for these species. In the three large industries to which it contributes — lumber, 

 pulp, and bark — it has become practically indispensable. 



During the last five years hemlock has ranked fifth in importance among the 

 lumber trees of the United States, being exceeded only by yellow pine, Douglas 

 fir, white pine, and oak. 



The durability of the wood depends very largely upon the nature of its use. 

 In contact with the soil it is very perishable, and is not well adapted for ground- 

 sills unless treated with a preservative. If kept in a dry place, however, it is 

 extremely durable. Even as outside covering it will give good service if placed 

 so that it dries out rapidly and thoroughly after being wet. There are instances 

 of hemlock barns which still stand after fifty or more years' use. Shaved hem- 

 lock shingles, if of good, straight-grained wood, and used on a moderately steep 

 roof, are practically as durable as white pine shingles. An important defect 

 of hemlock for such uses is its liability to check and split when exposed to the 

 sun. Hemlock laths are said to make a firmer and better wall than pine, though 

 harder to nail than either the latter or bass wood. 



Hemlock bark has been used in tanning practically ever since the beginning 

 of the industry in America. Oak bark is preferred, since it makes the leather 

 softer, more pliable, and less permeable to water than does hemlock ; but there 

 is not as much of it, and for many years its annual consumption in tanning has 

 been less than half that of hemlock. — A. D. W. 



Hippeastrum Elwesii {Bot. Mag. tab. 8614). — Argentina. Family Amaryllida- 



ceae. Tribe Amarylleae. Herb. Leaves with the flowers linear. Perianth pale 

 yellow, tube claret-coloured within ; lobes 3 in. across. — G. H. 



Hop Male, Humulus Lupulus L., Variation in the. By H. Wormald {J oar. 

 Agr. Sci. vii. Part 2, pp. 175-196, Sept. 1915 ; 1 plate). — Contrary to the opinion 

 current until recently, the Male Hop Plant shows considerable variation. Salmon 

 and Amos have shown that for the production of " well grown-out " hops a 

 certain number of seeds is of primary importance. Hence hopgrowers have 

 been recommended to plant a certain proportion of male plants in the hop gardens. 

 The author points out that for the purposes of pollination the two characters 

 of greatest commercial importance are (1) time of flowering, (2) suitability to 

 different types of soil of the male hop plant. He has examined about eighty 

 different plants for three seasons in regard to the two above-named characters, 



