1896,] Current Literature. 377 
vilts the branches bloom profusely, but the flowers are small and al- 
most never set fruit; the affected trees may linger for many years, and 
tarely die outright; the annual loss from this disease in Florida is 
about $150,000; the cause is unknown, but it is probably a contagious 
malady and incurable; affected trees should be dug up and burned. 
2. Die-back or exanthema: Caused by malnutrition, accompanied by 
improper drainage, improper cultivation, etc.; recognized by the very 
large dark pointed leaves and the reddish-brown stains on certain of 
the new-growth twigs, which later die back; brown eruptions occur 
abundantly on young and old twigs, all of which finally die back; mul- 
tiple buds form in the leaf axils; diseased trees bear little fruit, which 
is off color and commonly disfigured by the reddish-brown stain; an- 
nual loss from the disease in Florida about $100,000; withholding all 
oyganic nitrogenous manures, ceasing to cultivate, and mulching the 
soil have been found beneficial. 
3. Scab or verrucosis: Attacks principally sour oranges and lemons, 
the common sweet orange being exempt; probably introduced into 
America from Japan; shows as small excrescences on young leaves and 
fruit, at first pale, but soon coated with a dusky growth of Cladospor- 
tu, the parasite causing the disease; very much distorts young leaves 
and the fruits; loss chiefly from action on lemons, causing an annual 
loss in Florida of about $50,000; prevented on lemons by spraying 
young fruits from three to five timeswith ammoniacal solution of cop- 
Per carbonate. A 
4. Sooty mold: A black fungus, which follows the attacks of certain 
honeydew-secreting insects; recognized by the sooty black membrane 
formed principally over upper surfaces of leaves, 
steatly reduces productivity of trees, and the oranges formed are 
dly disfigured; annual loss in Florida from the disease about $50,- 
°0; spraying with resin wash has been found very effective, also fu- 
migation with hydrocyanic acid gas; a parasite fungus (Aschersonia 
‘ahitensis) promises to be a very great aid in combating the malady. 
5: Foot rot or mal-di-gomma: The most wi 
diseases: recognized by exudation of gum 
hear the base, resulting in falling off of th 
o. and around the trunk, the tree often be! 
Parently contagious and caused by some ml 
zee Neca sempe and disease may be prevented by using sour 
Tange stocks on lowlands and flat woods, and grape 
ig and dry pine lands; removing soil from around ae pag shee 
€ most effective treatment; annual loss from the dise 
about $100,000. 
