FLORIDA STATE HORTICULTURAL SOCIETY. 
99 
enough to blossom much, came out into 
excessively abundant bloom. The wither- 
tip fungus attacked the flowers and, the 
trees being in a weakened condition, fol¬ 
lowed down the flower clusters into the 
twigs, destroying a great many twigs, 
many of the larger branches and, in a 
good many cases, the whole tree, the fun¬ 
gus continuing down the trunk to the 
surface of the ground. In another case, 
more recently, several hundred budded 
trees were obtained from a nursery and 
kept for several weeks in a lath shed be¬ 
fore being set out. At the time they 
were set out the man in charge noticed 
brown spots near the bases of the cions 
on a good many of the trees. These rap¬ 
idly enlarged and finally girdled the trees, 
destroying quite a large percentage of 
those set out. In this case also the with- 
ertip fungus was to blame, having gained 
entrance either through some wound 
made at the time the top of the stock 
was lopped off, or through some of the 
little lateral shoots that started shortly 
above the bud on the cion, or through the 
wounds caused by their removal. An¬ 
other case was that of a little avocado 
tree growing in very poor, rocky soil, 
with no water except the scanty rainfall 
we had last year. No fertilizer of any 
kind was given to the tree and it made 
a very weak growth, losing its leaves this 
past winter before the new leaves came 
out. It blossomed quite abundantly and 
the fungus passed on into the twigs 
and is now entering into some of the 
large branches. 
I have contiued my work on nematodes, 
on which I made a report before the So- 
ciey two years ago, and have a few things 
that I would like to add. I have made 
several extensive trips to determine the 
distribution of the rootknot, and find that 
it is more widely distributed than any¬ 
body supposed, occurring as far north as 
New York, West Virginia, Michigan, In¬ 
diana, Nebraska, Colorado, Utah and 
California, thus being found in parts of 
the country where the winters are very 
cold, at times with the ground freezing to 
considerable depth. It also occurs in Eu¬ 
rope, Africa, Asia, East Indies, Australia^ 
New Zealand, Hawaii, West Indies, 
Mexico, Brazil and Argentina and 
doubtless elsewhere in South America. 
According to the reports of others 
and my own observations, it occurs on 
over 375 species of plants and if careful 
observations were made wherever it oc¬ 
curs, this number would doubtless be mul¬ 
tiplied many times. Nearly all of the 
large families of flowering plants are 
represented by plants that are subject to 
rootknot, while even the comptie, which 
is not a flowering plant, is not exempt. 
Of the cultivated plants, as I mentioned 
two years ago, beggarweed, peanuts, and 
velvet beans seem to be about the only 
important leguminous crops that are not 
injured, while among the grains, corn, 
sorghum, wheat and rye seem to be 
exempt. Oats, on the other hand, which 
in all my previous observations showed 
no signs of the disease, I have found to 
be subject in certain cases. I have tested 
further the effects of different fertilizers 
on the rootknot injury. Those fertilizers 
containing large amounts of potash I have 
found to be of value in that they reduce 
the ■ amount of injury and seem to act¬ 
ually reduce the amount of rootknot pres¬ 
ent, the plants not only having a more 
vigorous appearance, but actually show¬ 
ing smaller and less numerous knots. 
Kainit and Potassium magnesium carbon¬ 
ate are superior to sulphate of potash. 
Formalin treatment of the soil I have 
