Table 1 .--Modeled herbage production potentials for selected combinations of annual precipitation, presence or absence of limestone 

 soils, tree crown cover, and nitrate-nitrogen in the soil 



Annual precipitation, inches (cm) 



Soil N03 Cover 5 (13) 10 (25) 15 (38) 20 (51) 25 (64) 



Lb/acre Percent Forage production. Ibl acre (kglha) 



(kg/ha)' 







(0) 







169 



(189) 



430 



(482) 



744 



(833) 



1,096 



(1 228) 



1,482 



(1 660) 







10 



169 



(189) 



430 



(482) 



744 



(833) 



1,096 



(1 228) 



1,482 



(1 660) 







20 



169 



(189) 



430 



(482) 



744 



(833) 



1,097 



(1 229) 



1,483 



(1 661) 







30 



170 



(190) 



434 



(486) 



751 



(841) 



1,107 



(1 240) 



1,496 



(1 676) 







AD 



t oD 



^^UO ) 



A7'\ 

 ^ 1 o 



[DOU } 



O i o 



^s ID) 



1 907 



\ 1 OO 1 J 



1 ,UO 1 



[ 1 ( 1 







ou 





[dOO ) 







1 n 1 1 



1 ,U 1 1 





1 4Q1 



1 , H C7 1 



\ \ 1 U ) 



£L,\J \ D 





10 



(11) 







183 



(205) 



466 



(522) 



805 



(902) 



1,187 



(1 329) 



1,605 



(1 798) 







10 



183 



(205) 



467 



(523) 



807 



(904) 



1,190 



(1 333) 



1,608 



(1 801) 







on 





( dHO } 



OOd 





Q71 



\ \ uoo ] 





[ 1 DUo ; 



1 ,yoo 



[d \0 ( ) 







oU 



C.H i 



1077 \ 



Do 1 





1 nan 



1 1 00 1 \ 



(1 dd\] 



1 ,DUO 



/ 1 Rni \ 



[ I OU 1 } 



9 1 7R 

 d, \ / o 



10 4R7 \ 













DOO 



(Ml) 



1 OQR 



1 ,uyo 



/1 9Rn\ 



1 R1 R 



M R1 \ 



9 1 R7 



d, \ O 1 



\d 1 







(0) 







183 



(205) 



466 



(522) 



806 



(903) 



1,189 



(1 332) 



1,606 



(1 799) 







10 



195 



(218) 



497 



(557) 



859 



(962) 



1,266 



(1 418) 



1,712 



(1 917) 







20 



233 



(261) 



593 



(664) 



1,026 



(1 149) 



1,513 



(1 695) 



2,045 



(2 270) 







30 



312 



(349) 



796 



(892) 



1,376 



(1 541) 



2,029 



(2 272) 



2,742 



(3 071) 







40 



413 



(463) 



1,052 



(1 178) 



1,818 



(2 036) 



2,681 



(3 003) 



3,623 



(4 058) 







50 



463 



(519) 



1.181 



(1 323) 



2,041 



(2 286) 



3,010 



(3 371) 



4,068 



(4 556) 



10 



(11) 







197 



(221 ) 



502 



(562) 



868 



(972) 



1,280 



(1 434) 



1,730 



(1 938) 







10 



233 



(261) 



593 



(664) 



1,029 



(1 152) 



1,517 



(1 699) 



2,050 



(2 296) 







20 



377 



(422) 



960 



(1 075) 



1,660 



(1 859) 



2,448 



(2 742) 



3,308 



(3 705) 







30 



467 



(523) 



1,190 



(1 333) 



2,058 



(2 305) 



3,034 



(3 398) 



4,101 



(4 593) 







40 



482 



(540) 



1,230 



(1 378) 



2,126 



(2 381) 



3,135 



(3 511) 



4,237 



(4 745) 



20 



(22) 







211 



(236) 



538 



(603) 



930 



(1 042) 



1,371 



(1 536) 



1,853 



(2 075) 







10 



352 



(394) 



897 



(1 005) 



1,552 



(1 738) 



2,288 



(2 563) 



3,092 



(3 463) 







20 



475 



(532) 



1,212 



(1 357) 



2,095 



(2 346) 



3,089 



(3 460) 



4,175 



(4 676) 







30 



501 



(561) 



1,276 



(1 429) 



2,207 



(2 472) 



3,254 



(3 645) 



4,398 



(4 926) 



30 



(34) 







225 



(252) 



573 



(642) 



991 



(1 110) 



1,462 



(1 637) 



1,976 



(2 213) 







10 



408 



(457) 



1,039 



(1 164) 



1,796 



(2 012) 



2.648 



(2 966) 



3,579 



(4 008) 







20 



506 



(567) 



1,289 



(1 444) 



2,229 



(2 496) 



3,287 



(3 681) 



4,442 



(4 975) 



'SI units in parentheses, 



-"The table is asymmetric because maximum values of N03 and cover are not expected to occur simultaneously (see fig. 1) 



5 



