Results of a study on the effect of length of storage on germination 

 indicate that immediately after harvest, seed were slow to germinate, 

 requiring about 24 days to reach 50 percent germination (Fig. 20) . By 

 February, 50 percent of the seed sample germinated within 4 days. The 

 results suggest that an afterripening process occurs that speeds germi- 

 nation and increases the germination percentage as the length of storage 

 increases. Similar results were obtained by Van Shreven (1958) in a 

 study of S. townsendi'L seed. It is difficult to evaluate the effects of 

 length of storage on germination beyond 6 or 7 months since the epicotyl 

 of a large percentage of seed emerges even though stored in salt water 

 at 2° to 3° Centigrade. Experience has indicated that seed stored longer 

 than 1 year do not retain their viability. A study to develop techniques 

 to increase longevity of storage could prove beneficial. 



Samples of seed harvested 21 September 1971 at Oregon Inlet were used 

 to compare storage in estuarine water with distilled water. After 

 2 months storage, there was no difference in germination between the 

 storage treatments (Fig. 21). However, after 5 months, when the after- 

 ripening process was apparently complete, seed stored in estuarine water 

 had a significantly higher germination percentage than those stored in 

 distilled water. At least in some cases, storage in salt water enhances 

 seed germination. 



d. Planting Methods for Field Experiments . Several methods of 

 planting and incorporating seed have been used. In the first field 

 experiment with seed (1970) , the plots consisted of three rows of seed 

 planted in furrows 1.0 meter apart and 15.2 meters long. Since the 

 seedlings were confined to narrow rows, little growth per unit area was 

 produced during the first growing season (Tab. 14). The results of this 

 initial experiment indicated that seed could be successfully used to 

 establish S. alterniflora and that seed should be distributed evenly over 

 an area to give a better plant cover during the first growing season. 



In 1971, comparisons were made between the performance of seed applied 

 to the surface in a clay slurry (attapulgite) and seed broadcast by hand 

 and incorporated 1 to 4 centimeters into the substrate. At Oregon Inlet, 

 seed applied to the surface in the clay slurry produced a greater amount 

 of aboveground growth than those which were covered (Tab. 15). The seed 

 in the clay slurry germinated earlier and got off to a faster start since 

 temperatures on the surface were probably higher and the seedlings did 

 not have to emerge through a layer of sand. However, at Snow's Cut, seed 

 planted in the clay slurry produced almost no seedlings. There is a 

 greater tide range at Snow's Cut, and due to the regular flooding the clay 

 slurry containing the seed did not remain in place long enough for germi- 

 nation and rooting to occur. In adjacent plots, where seed were 

 thoroughly mixed with the substrate by raking to a depth of 1 to 4 centi- 

 meters, there was a good stand of seedlings which produced very good 

 growth (Tab. 15). It appears that broadcasting the seed and covering to 

 a depth of 1 to 4 centimeters is the best method to ensure a good stand 

 of S. alt ermi flora seedlings over a wide range of conditions. 



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