Results of Sthriblings Research 
ECONOMIC VALUE 
S-37 is a seedling rootstock for drupe fruits 
proven for more than ten years to be con- 
sistently more resistant to Nematode than any 
of the other standard resistant peach root- 
stock varieties, including Shalil, Yunnan and 
Bokhara. Standard varieties budded on S-37 
stock produce trees far more vigorous than 
those budded on Shalil, Yunnan, Bokhara, 
etc., and most important of all, this vigorous 
growth is consistently uniform throughout 
the orchards where Nematode exists. S-37 has 
been widely distributed, tested and acclaimed! 
State experimental stations in California, 
Colorado, Maryland, Tennessee, South Caro- 
line and Virginia have tested it and found it 
far more resistant than the others. A multi- 
tude of leading fruit growers, promologists, 
plant pathologists, nurserymen, horticul- 
turists, agricultural commissioners and farm 
advisors throughout California have testified 
as to its superior resistant qualities under ac- 
tual orchard conditions. These tests have 
proven that S-37 will thrive on all types of 
soil, both sandy and heavy loam, and will pro- 
duce commercial fruit wherever peaches can 
be grown. It is predicted that S-37 will soon 
replace all of the other resistant Peach root- 
stock in use. 
ORIGIN OF S-37 ROOTSTOCK 
In 1935 an experiment plot of three thou- 
sand seedlings of the ornamental flowering 
peach, Prunus persica var., in ten mixed color 
varieties, were planted in Stribling’s Nurseries 
Experimental Grounds at Atwater, California. 
This plot was set out primarily to discover 
some possible control for Crown Gall. The 
sandy soil in the plot was heavily infested 
with Nematode. In the course of the experi- 
ments, several of the three thousand flower- 
ing peach seedlings seemed to show marked 
vigor in growth. These few vigorous seedlings 
were seed sports—natural variations off of 
the parent plant with certain new and unique 
characteristics. The unique characteristic in 
this case was an apparent marked resistance 
to the Nematode in the soil. 
The next step was to see if this resistance 
could be propagated and used on a commer- 
cial scale. Buds were taken from the selected 
few seedlings found most resistant and a 
seed orchard was set out to reproduce the 
seeds. The seedlings thus asexually repro- 
duced were also found to be very resistant 
to Nematode, and successive generations were 
as well. The remarkable discovery was, that 
although there is naturally a lot of variation 
in propagation by seeds, these seedlings were 
uniformly and consistently resistant to Nema- 
tode and also to Crown Gall. Further selections 
were made, and the best was S-37, S-37 being 
the code number used in the experimental 
plot. A large budded seed orchard of S-37 
was then set out and it now produces all of 
the S-37 seeds used throughout the country. 
2 
S-37 (PLANT PATENT NO. 904) 
A Valuable Resistant Peach Rootstock 
Resistant to Soil Nematodes 
AVAILABILITY 
Production of S-37 rootstock has advanced 
on such a wide scale that it now is available 
in any quantity in most nurseries throughout 
the State of California in June budded va- 
rieties, or, in special cases, as seedling under- 
stock. Current prices will be gladly quoted on 
request. Advance orders on some of the 
budded varieties are your assurance of com- 
pletely filled needs. At present five grower 
nurseries are licensed to grow S-37 rootstock 
and all nurseries can obtain trees from Strib- 
ling’s Nurseries, or their licensed growers. 
For 1950-1951 season a complete variety 
listing will be available in both June Bud and 
Yearling trees. 
RESTRICTIONS 
The S-37 Peach Rootstock is protected by 
United States Patent No. 904, issued the sixth 
day of December, 1949. This patent insures 
the genuine strain of S-37 Peach Rootstock 
and governs its reproduction. Stribling’s Nurs- 
eries is the sole source of supply of S-37 
seeds and seedlings. It is illegal to directly 
or indirectly dispose of any S-37 seedlings or 
bud wood of S-37 Seedlings, or to permit its 
use, for the commercial or home propagation 
of trees, or for top working of any established 
trees without a written agreement with Strib- 
ling’s Nurseries. 
THE IMPORTANCE OF ROOTSTOCK 
SELECTION 
Today’s improved breeds of fruit trees are 
all budded or grafted on seedling or cutting 
grown understock (called rootstock) which 
produce healthier, more vigorous trees. 
These rootstocks are scientifically bred and 
developed to produce trees that will thrive 
under these varying local problems of soil 
conditions, climate, insects and disease. Some 
rootstocks thrive more in heavy soils, others in 
light sandy soils. Some rootstocks will tolerate 
lots of water, others must be well drained. 
There are still others that are used because 
they have a marked resistance to certain dis- 
eases and insects in some soils, such as nema- 
tode, crown gall and oak root fungus. 
After years of experience and research we 
have selected and developed rootstocks to 
meet any of these varying conditions en- 
countered in growing fruit trees. 
RESISTANT ROOTSTOCKS 
Resistant Rootstocks. Are rootstocks se- 
lected and planted for their resistance to 
insects and disease prevalent in certain areas 
of California. In general, the resistant root- 
stocks are adapted to a wider range of soil 
conditions and can be successfully planted 
in all areas where fruits can be grown. 
FRUIT VARIETIES LISTED ON PAGE 36 
T. B. STRIBLING, JR. 
Owner and Manager of Str:bling’s Nurseries since 
he founded it in 1911. 
S-37 Rootstock (Plant Patent No. 904). 
S-37 rootstock is the best all around peach 
understock for peach, nectarine and almond 
varieties because of its resistance to nema- 
tode, and its adaptability to sandy and heavy 
soils. S-37, because of its high resistant 
qualities and adaptability to all soil types, is 
rapidly replacing Shalil, Yunnan and Bokhara, 
which are other resistant peach rootstocks. 
Mariana 26-23. Mariana 26-23 is the 
best adapted all around rootstock for plums, 
prunes and apricots as it is a natural plum 
rootstock; resistant to nematode, oak root 
fungus and crown gall. In our research and 
field tests, we have found Mariana 26-23 to 
be the outstanding root for plum, prune and 
apricot and have discontinued growing the 
other plum and apricot rootstocks except on 
special orders or for specific conditions. Mari- 
ana 26-23 is also used as rootstock for some 
varieties of almonds in wet areas; however, 
Nonpareil almond does not make a good union 
on this rootstock. 
1613 and St. George Grape Understock. 
Are used in vineyard planting where Phyl- 
loxera and/or Nematode exist. These are 
available in rooted vines and must be grafted 
or budded to the desired variety after planting 
in vineyard. 
STANDARD ROOTSTOCKS 
The Standard Rootstocks. Are used and se- 
lected for their ease in obtaining a seed and 
cutting source and their ability under normal 
conditions to produce a thrifty, healthy tree 
when the desired variety is budded or grafted 
on them. Where no pest or damaging insect 
or fungus exists, the standard rootstock is 
very desirable. 
Lovell Peach rootstock is an example of 
such rootstock and it is ideal as a peach, 
nectarine and almond understock where 
nematode or other pests are not a problem. 
We have selected Lotis as our Persimmon 
understock, Mazzard rootstock for cherries, 
Northern California Black Rootstock for our 
walnuts, and special pear, pecan, apple and 
other seedling rootstocks for ability to produce 
the finest Growing Quality trees available. 
“Know your rootstock requirements before 
you plant.” 
