April, ’24] 
WATSON: NEMATODE CONTROL 
225 
of scale insects on palms and Ficus sp. One case of very slight injury 
to the newly formed leaves of Kentia belmoreana was observed. Table 
No. 2 (1). The house temperature at this time was 65 degrees and 
the spray was applied on a very dark day followed by several cloudy 
days. On bright, sunny days the emulsion has been used at 2% 
strength on Kentia sp. without injury to the foliage but is not recom¬ 
mended since the 1% strength is sufficient to give 95-100% control 
with one application. Besides killing the live scale on the plants this 
spray loosens the dead scale and old scale covering eggs so that syringing 
under pressure at the time of watering will rid the plants of both. 
The spray also spreads and sticks very well and will remain on the plants 
several weeks. For this reason young scale are prevented from becoming 
established, particularly Lecanium iessellatum Sign., which is viviparous. 
Leaves of plants sprayed are given a clear and healthy color and dirt 
or dust that collects on the plants is more readily washed off the sprayed 
plants than is the case with the unsprayed plants. 
The lubricating oil emulsion spray is equally effective in controlling 
the Fern Scale, Hemichionaspis aspidistrae Sign., but is not recommended 
because of the liability of injury to the foliage of the plants. See table 
No. 1 (7). 
President A. G. Ruggles: A paper will now be presented by Mr. 
J. R. Watson. 
CONTROL OF ROOT-KNOT NEMATODES ON FLORIDA 
TRUCK FARMS 
X • ■ •' • • • • • • • 
By J. R. Watson 
Abstract 
Starvation. Culture of an immune cover crop during the summer with constant 
cultivation to keep down weeds and prevent encysting. 
Soil Fumigation. Use of a combined treatment of sodiun cyanide and ammon¬ 
ium sulphate; Calcium cyanamid; calcium cyanide; sulphur. 
Heat as a control measure. 
Flooding as a control measure. 
Incidental control of insects in the soil. 
Perhaps some of the members may feel that a paper on nematodes is 
a bit out of place in a meeting of entomologists, but in our southern 
states, at least, some one must tackle the problem, and generally the 
choice lies between the entomologist and the plant pathologist, and a 
nematode is certainly more closely related to an insect than to a fungus. 
