EFFECTS OF FREEZES ON CITRUS IN CALIFORNIA 



285 



it is not too severely injured. In many cases where no beneficial 

 results were observed from wrapping the treatment was applied too 

 late, or the injury was so severe that no treatment could be effective 

 in saving the injured parts (fig. 12). 

 Where trees are treated in this 

 way following a freeze they should 

 be given no other treatment, unless 

 the trunks are whitewashed to pro- 

 tect them from sunburning. No 

 further treatment than the wrapping 

 is necessary for several months, or 

 until the new growth is well under 

 way and until bark that was killed 

 has dried out and clearly shows the 

 extent of the damage. As soon as 

 this time arrives, the wrappings 

 should be removed, the dead bark 

 thoroughly cut away, and the in- 

 jured patches thoroughly cleaned. 

 After this cleaning, probably the best 

 treatment is to first paint the injured 

 area with Bordeaux paste and some 

 weeks later with asphalt dissolved in 

 benzine. The use of Bordeaux paste 

 as a first treatment seems to be very 

 desirable, as it seems necessary to 

 use some sterilizing solution to pre- 

 vent the development of fungi. Fol- 

 lowing this treatment with a coating 

 of asphalt paint renders the wound 

 impervious to w r ater and gives a per- 

 manent finish to the treatment. 



Waxing and Painting Split Bark. 

 The covering of the splits in 

 the bark with grafting wax was 

 a very common practice. Some 

 growers used white lead instead of wax. Sometimes the bark was 

 wrapped after the waxing, and sometimes the waxing was the only 

 treatment given. Where there was a chance to compare waxed trees 

 with those that had not been treated, there was nothing to show that 

 the waxing had done good. It was practically impossible to get the 

 wax under the loose bark, and so the wax simply sealed up moist 



Fig. 12. Four-year-old Eureka 

 lemon, on which the split bark was 

 covered with grafting wax and 

 wrapped with twine. Treatment ap- 

 parently did no good because of 

 grafting wax. Loosened bark prompt- 

 ly wrapped with twine without other 

 treatment frequently healed on. Photo 

 by Tylor. 



