PROTECTION FROM FROST. 259 



13. We need a united system of general alarm for localities through- 

 out the valley. 



14. Wind-breaks, parallel with the flow of the cold stream air, are 

 an advantage in preventing radiation. 



15. Close wind-breaks, at right angles to the flow of cold air, will 

 form dams and cause low temperatures on the upper side. A block of 

 large trees below a block of smaller trees will have the same effect. 



16. Coal baskets or brush fires concentrated at these points will 

 drain off the cold air. 



17. Flowing water is a help, but is not sufficient in itself. 



18. Clean culture and a wet surface is the best condition of the soil 

 in times of danger. 



19. Trees that had suffered from lack of water at any time during 

 the development of the crop and those with a dry surface of the soil 

 suffered greatest injury. 



20. Firing of any kind is beneficial if there is enough of it. 



21. The cost need not be prohibitive for good results. 



22. Accumulative firing is better than single-handed. 



23. A single grower can succeed in saving his fruit with coal baskets 

 if he has enough of them. 



24. Be prepared to make more fires than you will likely need. The 

 unexpected sometimes happens. 



25. No grower should depend on his neighbors for heat or smudge. 

 Every gap is an injury to the whole. Besides, your neighbors may 

 not locate their fires so as to do you much good. 



26. Coal baskets can be made for about seven cents each. The 

 filling will cost about seven cents, where bituminous coal costs $10 per 

 ton, and you should have from twenty-five to fifty per acre, according 

 to location and size of grove. 



27. A. little burning straw is a snare and deceit. 



28. Straw smudge should be made with wet straw, should be dense, 

 and should cover large areas to yield best results. Dry straw is of 

 little value, except to help burn that which is very wet. 



29. The efficacy of smudging being dependent upon preventing radia- 

 tion in very dry climates, early lighting in such cases is imperative. 



30. A little dry brush is a great help in burning very wet straw. 



31. Green cypress boughs create a fine smudge. 



32. Most groves have a cold corner. Have some brush piles ready 

 to light at the critical hour — about dawn. 



33. Coal baskets should be full at the start. Coal will not ignite 

 readily in replenishing if a good bed of coals is not secured at first. A 

 reserve supply of coal may be very useful if the cold is long continued. 



