AMONG SCHOOL GARDENS 



Stress upon their relative heating capacity is the 

 more important. I n passing, perhaps there should 

 be a word of caution about using any of them 

 that have been allowed to lie too long exposed to 

 sun and rain so that their soluble constituents, 

 especially their nitrates, may have leached into 

 the ground and their other nitrogen compounds 

 may have passed into the air in the well-known 

 ammonia fumes. Neither should any fertilizer 

 be allowed to become corrupted by mold or spores 

 of toadstool or mushroom. In one instance that 

 came under the author's observation, a florist 

 lost two-fifths of a crop of greenhouse roses, mean- 

 ing hundreds of dollars in lost sales and cost of coal, 

 because his son hastily selected a pile of manure 

 and mixed it with the fall supply of earth for the 

 greenhouse benches. The boy had been sent to 

 inspect the manure before purchasing. He had 

 arrived at dusk of a fall day and visited the heap 

 with a lantern. His hasty examination of it satis- 

 fied him. He paid for it, had it carted home, and 

 had it in the greenhouse before his father discovered 

 spores of mushrooms. The older man had picked 

 up his knowledge of flowers. He thought he would 

 better take the risk than lose time, labor and 

 money. In the end, it was an expensive decision. 

 Among manures, that from cows is known as 

 cold.* Hen manure is very hot and should always 



* It contains the largest per cent of water (75.3) while sheep ma- 

 nure has less (59.5 percent) and hen, least (56 per cent). These last 

 two may have the same amount of nitrogen, nearly twice that of cows. 



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