14 N. H. EXPERIMENT STATION [Bulletin 319 



and needs heavy grazing U) control regrowth. Sweet fern is most 

 difficult to control. The bark is so thick that burning is very slow. 

 The roots break off and new plants start at the joints when pulled. 

 Several new sprouts start when the plants are cut off. Cattle do not 

 browse on the new shoots so there is little control through pastur- 

 ing. Hardback is readily controlled by each of the three methods, 

 i'ulling early in the spring gives satisfactory results but requires a 

 great deal of labor. 



Labor required per acre by the three methods is as follows : Pull- 

 ing, 100.9 hours ; cutting, 68.2 hours ; burning, 57.4 hours. On two 

 farms wath a heavy stand of sweet fern {Myrica asplenifolia) mixed 

 with some hardback (Spiraea torncntosa) and meadow sweet {Spiraea 

 latijolia) pulling required 57.7 hours per acre, cutting required 56.6 

 hours per acre, and burning 42.5 hours per acre. Under these cir- 

 cumstances with better control of brush and no standing brush left 

 to bother, pulling seems to offer best opportunity for control. 



On three farms with a heavy almost pure stand of hardback {S. to- 

 mentosa) it took 70.8 hours to pull, 51.5 hours to cut, and 14.3 hours 

 to burn. The number of new shoots that start does not vary much 

 on the three plots, but cutting has the disadvantage that the stubs 

 are left to check grazing around the old plants and burning leaves 

 the old stalks to prevent close grazing. Usually one season is long 

 enough to decay them and they break off easily. 



On three farms with a mixed stand of brush consisting of junij^er 

 {J. communis), hardback (S. tomentosa), meadow sweet (S. latijolia), 

 blueberry {V . pennsylvanicvm and V. vacillans, Ioav bush, and V. co- 

 rymbosum and V. atrococcinn. high bush) and sweet fern (.1/. asplen- 

 iiolia) and little or no gray birch, pulling was very difficult and 

 required the most labor of any class of clearing. Pulling took 159 

 hours, cutting 54.7 hours and burning 50 hours per acre. 



On four farms the stand of gray birch was too large to warrant 

 pulling. This was cut on all plots, pulling and burning only the small- 

 er brush. The labor involved on the various plots was not greatly 

 different, since all plots were treated somewhat alike. On the so- 

 called pulled plot clearing took 315 hours, on the cut plot 277 hours 

 and on the burned plot 196 hours. 



This amount of labor does indicate that in order to warrant clear- 

 ing of large brush the pasture need must be great and the soil such 

 as will provide good pasturage. 



Ferns and brakes can be controlled by twice-a-year cutting. June 

 and August. The season was too dry in 1939 to permit any burning. 

 Two farms of the 18 have k»w bush blueberries, which are a problem, 

 and another year spring and fall burning will be tried on these farms 

 to determine the possibility of killing l)lucberries in this manner. 



Simply cutting brush will not necessarily improve pasture. Much 

 i>f the result would be simply a change in the kind of herbage or 

 substituting one kind frir another frequently worse. To raise the 

 level of fertility to a point somewhat above that re(|uired by much 

 of the brush encountered on pastures, lime and fertilizer were added 

 in fixed amoimts. Tn addition to raising the level of fertility to in- 

 duce the spread of good pasture plants, the effect of different fer- 



