do not look vigorous enough to last until rota- 

 tion age. Only 11 of the original 128 seedlings 

 are in the dominant-codominant crown class 

 (table 2). Competing trees in the dominant- 

 codominant crown class in 1976 included yellow- 

 poplar, chestnut oak, cherry, aspen, and red 

 maple. 



None of the cultural treatments resulted in a 

 dramatic increase in height growth compared to 

 that of the check trees. Only the mulch treat- 

 ment was consistently better than no treatment 

 (table 1). 



Blxick walnut— Site apparently was a major 

 factor influencing establishment of the black 

 walnut seedlings (tables 1 and 2). Even though 

 the sources of the planting stock were slightly 

 different for the good and medium sites, the 

 results indicated that the large differences 

 between sites should probably be attributed 

 mainly to site effects. 



Only 11 percent of the original seedlings on 

 the two blocks on the medium site survived. 

 Only one of these remaining trees was in the 

 dominant-codominant crown class (table 2). 

 Intermediate and suppressed trees probably will 

 not make it to rotation age. Average height of all 

 surviving walnut trees on the lower site areas 

 was 14.0 feet (4.2 m), and the average diameter 

 was 1.1 inches (2.7 cm). 



Sixty-one percent of the original seedlings on 

 the two blocks on the good site survived. 

 Twenty-five of these remaining trees were in 

 the dominant-codominant crown class (table 2), 

 and 17 were more than 25 feet tall. Average 

 height of all trees on the good site areas was 23.5 

 feet (7.16 m), and average diameter was 3.1 in- 

 ches (7.8 cm). The tallest walnut tree was 43.2 

 feet (13.17 m), and had a dbh of 4.7 inches (11.9 

 cm). Another of the larger walnut trees was 

 already bearing fruit (fig. 1). 



All cultural treatments showed a distinct ad- 

 vantage over the check trees on the good site 

 areas, the mulch treatment having the best 

 average height (table 1). Only 2 of the 25 trees in 

 the dominant-codominant crown class were 

 check trees (table 2). Differences were not as 

 distinct on the medium site areas. Again 

 though, there were too few surviving trees to 

 make sound conclusions regarding treatment 

 effects. 



Figure 1.— Black walnut tree 35.5 feet (10.8 m) 

 tall and 5.7 inches (14.5 cm) dbh, 13 growing 

 seasons after planting. Original seedling re- 

 ceived mulch treatment on good site area. 



Discussion 



Seedlings planted in a recently clearcut area 

 must compete with fast-growing trees, shrubs, 

 and sprouts that have established root systems. 

 To establish valuable species such as red oak 

 and black walnut, the planted seedlings must be 

 kept free of competition through cultural 

 treatments that are usually expensive to apply. 



Krajicek (1975) found that, after seven grow- 

 ing seasons, survival of black walnut seedlings 

 planted in cleared forest openings in Illinois did 

 not differ by competition-control treatments. 

 He also found that the trees grew somewhat 

 larger where all competing vegetation was con- 

 trolled, but almost as large when only her- 

 baceous competition was controlled. 



Although our study did not provide conclusive 

 evidence, the results do warrant some general 



4 



