Webber: The: Improvement of Root Stocks 297 
perience of the reaction of buds on 
different stock such as referred to 
above. 
DIFFERENCES INHERENT IN STOCKS 
Will the small trees continue to re- 
main small? Certainly the evidence 
thus far indicates that this is very 
likely. The probabilities are that they 
will. Dr. Reed of the Citrus Experi- 
ment Station carried out a series of ex- 
periments! with a considerable number 
of sunflower plants that has a bearing 
on this phase of the problem. In this 
group of sunflowers, exact measure- 
ments of height were made of each 
plant every week from the time it was 
a few inches high until it reached ma- 
turity. The analysis of the data of 
growth obtained showed a well marked 
tendency of the plants to retain their 
same relative rank as to size through- 
out the period of growth. Plants 
which were small at maturity were 
generally small in the beginning and 
those which were large at maturity 
had a well marked superiority from 
the start. The evidence indicated 
that height and vigor of growth were 
determined not by chance but by some 
definite inherent factor in the plant 
itself. The same is doubtless true with 
citrus seedlings of the various species 
such as those used for stocks and if the 
cause of the different sized nursery 
trees is to be attributed primarily to 
the influence of these stocks as seems 
probable, then it is also probable that 
the difference is due to causes inherent 
in the different stocks and that the 
same relative rate of growth and size 
will be maintained in the majority of 
the plants. 
While the evidence is yet incomplete, 
we are probably justified from what 
evidence we have in speculating some- 
what as to what this means in our fruit 
industries. Frequently, almost every 
tree in an orchard will be a fine good 
grower and fruiter, giving a uniform 
orchard. Again, an orchard equally 
well handled may be very ununiform 
‘Reed, H. S. Growth and variability in Helianthus. 
p. 252. 
having some good trees, some poor ones 
and some of intermediate character. 
This difference could be accounted for 
by assuming that the good orchard 
chanced to be from trees grown on stock 
that happened to come from seeds of 
good stock trees or that they had been 
taken from a nursery where in filling 
the order of size only the large trees had 
been dug, which would be the ones 
naturally on good vigorous stocks. 
The remaining slower growing trees 
from such a nursery would ultimately 
reach the required size and be sold and 
planted in another orchard which 
would likely give an uneven orchard 
with good and bad trees. 
Some growers will be inclined at first 
to think that their experience is con- 
trary to this and that the small tree is 
more likely to be fruitful while the 
largest trees are likely to spend their 
energy in vegetative growth. They 
must remember that this experience 
was gained before buds of selected type 
were used. Mr. Shamel has demon- 
strated that some types of our varieties 
tend to produce rapid growth and little 
fruit while others produce good growth 
and are fruitful. The results the writer 
is explaining, however, were obtained 
with the use of buds taken from the best 
fruiting types and it is not likely that 
this type will be changed materially by 
the stock other than in size of growth. 
NEW NURSERY METHODS SUGGESTED 
If the results of these experiments 
are correctly interpreted by the writer 
it means that our nursery methods in 
citrus propagation must be materially 
changed. 
(1) We must no longer grow merely 
sour stock or sweet stock and the like. 
The process must be carried farther and 
good stock varieties of sour orange and 
sweet orange must be discovered and 
named as stock varieties and every 
nurseryman should then use seeds from 
these varieties known to produce good 
stock seedlings. The trees of these 
varieties from which seeds are to be 
American Journal of Botany, Vol. 6, 1919, 
