categories, although in October and November, nonrooted culms had higher survival than 

 rooted culms. No explanation for this is known. Comparative growth rates (Fig. 29) showed 

 that rooted transplants exhibited less transplant shock and began regrowth more quickly in 

 summer. However, after a short period, this difference was no longer evident. The 

 conclusion was that there is no advantage to selecting rooted over nonrooted stock. 



Bitter panicum culm size had a decided effect on survival (Table 37). The small size 

 included the smallest available primary culms, generally too slight for mechanical 

 transplanting. Small-culm survival was significantly less than for larger, more robust primary 

 culms, which were the typical size of fertilized nursery stock or young expanding wild 

 stands. Small culms are typically found in old, stabilized stands. Fertilization will increase 

 the size considerably. The reason for the differential survival is unclear but may be related 

 to relative amount of food storage. In selecting transplant material during winter, larger 

 primary culms should be selected over smaller primary culms. 



Table 37. Survival of bitter panicum primary culms on north Padre Island. 1 



Size 



Total length 

 (feet) 



Average culm weight 2 

 (grams) 



Percent survival 3 



1973 



1974 



Mar. 



Jan. 



Feb. 



Large 

 Small 



>2.0 

 <1.0 



25 to 30 

 5 



79 a 4 

 5c 



77 a 

 10 c 



78 a 

 26 b 



1. Previous year's growth. 



2. All but terminal leaves dry; culm brittle. 



3. N = 150 plants, March; N = 100, January and February. 



4. Figures sharing common letters are not significantly different (Pq gg). 



During fall and spring, two basic bitter panicum culms are available: primary culms and 

 tillers (Fig. 30). Primary culms consist of the previous year's growth, and are mature, have 

 flowered, and are generally dry and brittle. Most lower leaves are dead, although terminal 

 leaves may remain green. In areas of light sand deposition, the culms are often a yard or 

 more long. In contrast, tillers during the same period are actively growing; the leaves are 

 green and the culm is succulent, but the size is usually smaller. During spring through fall, 

 tillers are abundant. By fall, many have matured, flowered, and become primary culms. 

 Comparison of survival and growth of tillers versus primary culms (Table 38 and Fig. 29) 

 shows that tillers with new growth were a superior choice over primary culms from late 

 spring through summer. When transplanted to the beach during this period, tillers responded 

 with rapid establishment and growth. However, from fall through spring primary culms were 

 the best choice. During this period, tillers began growth quickly after transplanting, 

 especially during warm weather, but soon became semidormant and many did not survive 

 through spring. 



Ill 



