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by natural fall of leaves before cold weather, as we see in most other trees, bat on 

 the contrary, the trees maintain their green foliage and keep pushing out young 

 leaves until a severe frost occurs and completely checks growth. This sudden check 

 and its effects upon the vitality of the plant produce, in my opinion, the disease called 

 yellows. 



It is in the power of the cultivator, in some cases, to modify the 

 conditions which encourage late growths, as well as to lessen the evil 

 effects which result from frosted growths. It is readily apparent that 

 trees set in constantly damp or very rich soil will have their growing 

 season prolonged beyond those planted in dry or poor soils. It is also 

 evident that in districts where the season for active growth is compar- 

 atively short, the soil should be well drained and manures sparingly 

 applied, and only in spring. In such cases stimulating culture should 

 not be prolonged through late summer, and even should weeds appear 

 they should be mowed over with a scythe rather than to disturb the soil 

 by cultivator or plow. 



But something can be done even with plants that have been injured 

 by the freezing of unripened growths, and that is the immediate re- 

 moval of the injured shoots, pruning them back to sound wood. If this 

 is performed in time the plant may escape further injury. 



In some parts of Florida the orange trees occasionally suffer from 

 slight frosts. During an unusually severe frost a few years ago many 

 of the young orange groves suffered quite severely from freezing of 

 succulent shoots. Hundreds of plants were destroyed and were re- 

 moved during the following summer, and hundreds of others lingered 

 on for a time, making sickly, yellow-leaved shoots, indicative of the 

 cause of their unhealthiness. A prompt removal of the injured shoots 

 would have saved most of these trees from utter destruction. 



One of the most effectual methods of hastening the maturity of yearly 

 shoots is that of pruning the roots, or by restricting their growths. 

 The restriction of root growth is applicable to plants in pots or tubs. 

 Florists recognize the fact that, with many kinds of plants, the best 

 flowering results are obtained when the pots in which they are growing 

 become well filled with roots. When this condition is reached vigorous 

 growth is checked and flower buds are produced in profusion. With 

 some perennial plants this cramped condition of roots is allowed to 

 exist for years, the plants being stimulated during the period of wood 

 extension by applications of liquid manures. 



Pruning the roots to hasten maturity of wood growth is of long and 

 successful practice. In no instance have we seen it so marked as when 

 applied to the roots of Asiatic conifers, and also those of our own 

 Pacific coast. These plants have a tendency to make late growths 

 during the moist autumn weather of the Eastern States, and this 

 growth is mostly destroyed by early winter frosts. A marked instance 

 is recorded where an avenue of the Japan cedar, Cryptomeria Japonica, 

 had each alternate tree root-pruned in August, which completely 

 stopped their growth for the season. The trees not operated upon 

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