22 
Upon crashing a mature, pregnant worm various forms of micrococci 
are visible by the microscope as existing within the Anguillula, evi- 
dently not hurtful, and when seen exterior to the worm seem not preju- 
dicial to its life ; but more study is needed on this point. 
8. Use of Vermicide Fertilizers. 
Experiments looking to the adoption of some mixtures capable of de- 
stroying the worms while in the root tissues have not proved a success. 
The use of smaller quantities per acre than one-tenth of 1 percent, of 
the surface soil for 1 foot in depth and 10 feet radius to each tree- 
about a ton to the acre— produced no perceptible effect on the disease, 
and a greater amount injured the trees. 
The use of bisulphide carbon, kerosene emulsion, and various arsen- 
ical solutions destroyed so great a percentage of the trees that on that 
account, and the expense of application, it was abandoned. 
Alkaline mixtures have done better, and will bear repetition, espe- 
cially the sulphites and muriates. 
For nursery stock, it no doubt will pay to thoroughly incorporate 
some of these chemicals with the soil some weeks before planting seeds, 
cions, or young trees, using it at the rate of at least one-tenth of 1 per 
cent, of the surface soil cultivated. 
Alkaline fertilizers, as hard- wood ashes, muriate and sulphate of pot- 
ash, kainite, or ash element produce a hard growth but little, if any, 
affected by the root-knot. Usually the fertilizer is applied in too small 
a quantity. Not less than 3,000 pounds to the acre should be used to 
produce the required effect, one-half in December, the remainder in 
May. 
A fertilizer containing a small percentage of carbolic acid, carbolates^ 
thymol-cresol, or an easily decomposed sulphite would no doubt be valu- 
able in this infected section. 
9. Non-infected Stocks. 
After all, I believe the use of trees that are not susceptible to the 
root-knot, for stocks on which to graft or bud the susceptible varieties 
is the proper solution of the root-knot problem. The matter of location, 
soil, fertilizer, and prevention then need not worry the intending or- 
chardist. Find the disease-proof tree and the thing is done, and most 
of my experiments have been directed to secure in some measure this 
result. 
It is, perhaps, too soon to say that complete success has been realized, 
but the gain is perceptible. 
For the Orange I can recommend the hardy bitter-sweet or sour 
species as nearly disease-proof and a vigorous grower. 
The Citrus trifoliata and the Japanese " Unsliiu," or Satsuma, both 
seem resistant, but the time of trial has been too short. This last is a 
slow grower, with dense roots, and promises to be the best of any of the 
