increased yields over the control in every treatment, and addition of phosphorus and 

 potassium usually increased yields of roots, shoots, and tillers. Roots responded even more 

 than shoots to a complete fertilizer. Treatments 180-120-120 (Nitrogen-phosphorus- 

 potassium) and the more economical 120-120-120 resulted in maximum shoot growth. 

 Maximum root growth, desirable in newly transplanted stands, resulted from the 60-120-60 

 treatment. A compromise level of 120-60-60 combined high yields of roots, shoots, and 

 tillers. 



In contrast to sea oats, some fertilizer treatments did not increase bitter panicum yields 

 (Table 48). Also, the response to relative levels of phosphorus and potassium at high 

 nitrogen levels was the reverse of that for sea oats. The most important nutrients for bitter 

 panicum were nitrogen and potassium, whereas nitrogen and phosphorus were most 

 important for sea oats. The root system of bitter panicum made up a very small part of the 

 total plant weight. Best root weight came from the 180-60-60 treatment, producing a root 

 system comprising only 13 percent of the total dry weight. However, sea oats roots in some 



Table 48. Yield of shoots and roots, and tiller production of bitter panicum 

 for various fertilizer treatments in greenhouse. 



Fertilizer Treatment 



Yield 



Tiller production 

 (per 10 culms) 



Nitrogen 



Phosphorus 



Potassium 



Shoot 



Root 





(pounds per acre) 





(grams per 



10 plants) 

















22.0 



2.8 



19.4 



60 











27.4 



4.2 



32.5 



120 











23.6 



3.8 



21.8 



180 











21.2 



3.7 



20.6 



60 



60 



60 



22.8 



3.4 



35.0 



60 



120 



60 



21.1 



3.0 



21.8 



60 



60 



120 



23.2 



4.1 



23.3 



60 



120 



120 



23.8 



3.4 



20.0 



120 



60 



60 



21.8 



3.9 



27.1 



120 



120 



60 



31.4 



4.2 



21.9 



120 



60 



120 



40.0 



4.6 



25.8 



120 



120 



120 



27.6 



4.3 



22.5 



180 



60 



60 



37.8 



5.6 



20.0 



180 



120 



60 



21.6 



2.5 



18.4 



180 



60 



120 



26.2 



3.9 



19.5 



180 



120 



120 



21.1 



3.2 



17.8 



137 



