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ROOT ACTIVITY 



It is commonly known that the function of root systems is to supply vrater 

 and nutrients required for synthesis of food for tree and fruit grovrth. However, 

 the active part of the root system in this respect is not the large main roots 

 but the microscopic roct haii's that are in intimate contact mth small colloidal 

 particles of clay and humus. It is these root hairs that actually absorb water 

 and nutrients from the soil. 



Root hairs are short lived structures and often die within a week or less. 

 Thus, they must be constantly formed so that the tree will get sufficient water 

 and nutrients. These new root hairs develop continuously throughout the season 

 whenever temperature, moisture and aeration of the soil is favorable. Research 

 findings shovr that root growth is very limited during the viinter months, therefore, 

 most of these root hairs if not all must be regenerated at the beginning of each 

 gra\ii±ng season. 



Growers know that fruit trees do poorly or fail to survive on soils having 

 inadequate drainage. In such soils, at sometime during the growing season the 

 amount of oxygen in the soil is insufficient for formation of new root hairs. 

 Without oxygen root hair grovrth cannot occur. A representative silt loam soil 

 when in optimum condition for plant growth contains approximately ^0% pore space 

 being less for sandy soils and greater in soils containing clay. For optimum 

 conditions for root hair growth about half of this pore space should be occupied 

 by water and the rest by air. 



Early root activity is necessary for adequate moisture and nutrient uptake 

 by fruit trees before bloom, Vfithout this, spur leaf area will be small and fruit 

 set may be reduced. Sufficient root activity early in the growing season necessi- 

 tates good soil aeration and soil management practices. In wet seasons, trees 

 planted on poorly drained soils may be water logged during the first part of the 

 growing season. In such instances, root hair activity vail be confined to the 

 surface layer and thereby the leaves and fruit may suffer for the lack of oxygen 

 and nutrients. These trees^ unless the soil is tile drained, are apt to be non- 

 profitable to the grovifer. 



Growers should strive to apply their fertilizer to the fruit trees at least 

 tiiro to three vfeeks before bloom in order that the root hairs will be supplied 

 with sufficient nutrients for uptake, 



M. J. Lord 



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POMOLOGICAL PARAGRAPH 



Tree Girdling by iJice 



The writer has noted very little girdling of fruit trees by mice in orchards 

 visited during February, Apparently many fruit grovrers conducted a thorough 

 baiting program because mice were abundant in most orchards last fall. This does 

 not mean, however, that growers do not have to be on the alert for signs of girdl- 

 ing, ffice may have caused considerable damage in some orchards, 



Editor 



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