was higher in summer than winter, with only a short period of transplant shock. The plants 

 began growth quickly and were trapping sand within 2 to 3 months. In contrast, winter 

 transplants became dormant, most or all leaves died, and growth did not begin until late 

 spring. Fall and early winter plantings in 1972-73 and 1973-74 exhibited high initial 

 survival, as evidenced by new shoots emerging during late winter, but early spring mortality 

 was pronounced. Survival curves, comparing summer (August) and winter (November to 

 January) bitter panicum growth are shown in Figure 29. 



Probably the least desirable time to plant bitter panicum is in fall. Plants will remain 

 mostly dormant until the following spring, and vigorous growth will not begin until nearly 

 6 months later. During this 6-month period, the chances for inundations, drought, and sand 

 burial to occur are increased over a spring or early summer transplant, which will start 

 growth quickly. By mid-summer, culms planted in spring were nearly equal in size to those 

 planted the previous fall (Table 32). If environmental conditions are favorable, the best time 



Table 32. Growth of bitter panicum transplants on 1 July 1974. 1 



Planting date 



Days after planting 



Tillers per plant 2 



Mean weight per plant (grams) 3 



17 Nov. 1973 



226 



7.0 a 



15.4 



14 Dec. 1973 



199 



6.5 a, b 



12.5 



15 Jan. 1974 



167 



5.5 c 



14.7 



11 Feb. 1974 



140 



5.8 b, c 



15.8 



16 Apr. 1974 



76 



6.1 b,c 



12.8 



1. Culms were transplanted at a north Padre protected site on dates indicated but not fertilized. 



2. All exposed tillers, including those recently emerged; N = 90 plants per month. 

 Figures sharing common letter are not significantly different (P« q»). 



3. Oven-dried weight of exposed (aerial) growth only; N = 24 plants per month. 

 No significant difference (P „,.). 



to plant is from late winter to early summer. There are no concrete guidelines on when to 

 plant bitter panicum; problems are encountered in summer or winter (Table 33). All major 

 plots were planted in winter and spring (through April); none has been tried in summer. The 

 hot climate for physical labor and rapid drying of the substrate make summer planting 

 undesirable. 



Similarly, sea oats was successfully planted in the summer of 1973. However, January 

 and February seems the best time to plant sea oats on either end of the island, but any time 

 that soil moisture is high and soil salinity low, good results are possible. Again, the season is 

 not a strict influencing factor. 



Results of 70 experimental beach plantings of sea oats indicate a survival rate of 

 50 percent or better and should be considered excellent; 25 to 50 percent survival is very 

 good. Only 3 of 70 plantings had a survival rate greater than 75 percent; 12 had a survival 

 rate of over 50 percent; and 30 had greater than 25 percent survival. The remainder were all 

 25 percent or less. 



107 



