359 
instances from the germination of spores on the*under side the leaf. 
For this reason it is essential that the under surface receive the most 
thorough treatment. In the experiments here described four nozzles 
were used, viz, the Climax, the San Jose, the Cyclone, and the Improved 
Yermorel, and their adaptation to the work noted. They are all good 
nozzles, but when used with eau celeste mixtures a serious defect is found 
in all of them. The corrosive action of this spray, whether the latter be 
formed according to the modified formula or not, destroys the brass 
netting of the Climax nozzle and the brass plate containing the slot of 
the San Jose. The action on the other nozzles is similar, but the brass 
being thicker the openings enlarge less rapidly. The manufacturers of 
the Climax nozzles state their intention to supply aluminium nets for 
them, which will probably withstand the spray. This is a more impor¬ 
tant matter than it at first appears, and is especially so to Californians. 
In California fewer applications of fungicides are required than in the 
East, because of the partial absence of summer rains along the south¬ 
ern Pacific coast, but these applications should be more thorough. To 
properly spray a tree Avith one or two applications the spray must be 
fine, uniform, and carefully applied. To form this spray the nozzles 
used must be in good condition, Avliich is not true Avhen the openings 
are enlarged j in this case the liquid falls on the foliage in coarse drops, 
which run together and dry. When large areas are thus wetted the 
fluid will often u creep’ 7 or u crawl 7 ’ when drying, as paints do Avlien 
water is accidentally mixed with the oil. In this way the copper salts 
are brought together and dried in a few large areas instead of being 
distributed, over the leaf in small drops which dry where they fall. 
With enlarged openings in the nozzle much of the leaf is therefore left 
without the protection of the fungicide, Avliile Avith the fine spray the 
numerous collections of dried copper are distributed by the humidity 
cf the atmosphere or dews and fogs to all parts of the leaf surface. 
To those who have applied the resin washes to citrous trees it will 
be apparent that the mode of applying sprays for fungi is quite differ¬ 
ent from that followed for scale insects. For the latter an effort is 
often made to uniformly coat the branches and foliage with the mix¬ 
ture, as the nature of the spray used will alloAv of this even Avhen the 
parts are completely wetted. With the copper Avashes, however, the 
parts should be finely sprayed and not overwetted if the attacks of 
fungi are to be prevented in the most satisfactory manner. Foliage 
thus overwetted by almost any of the copper sprays, and especially by 
eau celeste, is apt to be more or less burned. Prune trees have been 
entirely defoliated Avhere the spray Avas too coarse. 
If the San Jose or Climax nozzle be used, the perforated plates and 
brass-wire screens should be replaced as soon as corroded. With the 
Cyclone nozzle no arrangement is found for a renewal of the corroded 
parts. Hence this nozzle, to be satisfactory, should be made of noncor¬ 
rosive metal. It presents one very desirable feature, viz., the spray is 
23192—No. 4-3 
