It is known that either fall- or spring-planted walnuts germinate
readily if the nuts are viable and if those planted in the spring are
properly stratified over winter. To find out just what effect spring and
fall planting has on germination and to compare various methods of
stratification, three seedlots were given the following treatments on
November 28, 1940:
1. Planted in seedbeds 5. Stratified at 65-75 deg. F
2. Stratified outdoors 6. Stored dry at 45-50 deg. F
3. Stratified at 38-40 deg. F 7. Stored dry at 45-50 deg. F
4. Stratified at 45-50 deg. F subsequently soaked in
water prior to planting
Nuts from the three seedlots were kept separate and planted in random
plots in three seedbeds. Each treatment was therefore represented nine
times with a total of 162 nuts in each treatment.
To determine whether time of outdoor stratification has any effect on
germination and emergence, three other seedlots were treated as follows:
1. Planted November 28, 1940 5. Stratified January 30, 1941
2. Stratified November 28, 1940 6. Stratified February 20, 1941
3. Stratified December 19, 1940 7. Stratified March 13, 1941
4. Stratified January 9, 1941
These three seedlots were also planted in three seedbeds with a total of
135 in each treatment.
With one exception, all nuts in the two tests were planted April 3,
1941. One of the two lots stored dry was soaked in water for five days,
then planted April 7. Seedbeds were equipped with screen wire cloth at a
depth of 10 inches.
~Results~: In both tests, fall nut planting resulted in the best
germination. Germination was higher for nuts planted in the fall than
for nuts stratified on the same day for spring planting, although the
difference was significant only in the second test. Outdoor
stratification produced the best results, followed in order by indoor
stratification at 38-40 deg. F and 45-50 deg. F. None of the nuts stored dry
germinated. Time of stratification proved to be important. Any delay
after November 28 resulted in reduced and retarded germination and
consequently smaller seedlings.