138 HOETICULTURAL MANUAL. 



(1) Those that flower on the same season's growth, such 

 as the rose, hardy hydrangea, privet, mock-orange, and 

 tamarix, should be cut back more or less severely in the 

 dormant season. This cutting hack of the new growth, 

 and in some cases still lower, increases the number of new 

 shoots on which the flowers appear. In the North and 

 Northwest, where the best hybrid roses and such shrubs 

 as Spirma callosa are not hardy in open exposure, the 

 winter covering is easier when severely cut back to prepare 

 for blooming the next summer. In milder climates where 

 the natural shape can be retained the needed supply of 

 bearing wood can be kept up by merely cutting back the 

 growth that reaches out beyond the line of symmetry and 

 shortening some of the inside growth. 



(3) Many of our best shrubs bear flowers on the points 

 or top of new growth that starts from wood of the preced- 

 ing year's growth, like the grape and quince; others 

 develop flowers on the preceding year's growth. With 

 these classes it is evident that cutting back the top will 

 remove the bearing wood, especially when cut below the 

 new wood. Hence such shrubs are headed in as soon as 

 the flowers fade. This light cutting back of points of 

 growth starts an additional growth of new shoots to flower 

 the next spring. Some well-known shrubs of this class 

 are flowering almond, snowball, weigelia, exochorda, 

 forsythia, Prunus trilola, lilac, tamarix, and some spirsas. 



(3) A few well-known species, such as barberry, cara- 

 gana, white fringe, bush honeysuckle, and kalmia, do not 

 need pruning except when they get some age, when the 

 pruning consists in cutting out some of the old wood, as 

 in pruning the currant and gooseberry. 



As a rule, in about all shrub pruning the operator must 

 observe from actua,l inspection whether the flowers grow 

 on the ends of terminal or lateral shoots of that season's 



