1284 l-'ORACI". CK()I'S, MI;AI)0\VS A.XD PASTI'RICS 



The above observations relate to i^rasslands very irregularly planted 

 with birch trees, the roots of which spread out near the surface of the soil 

 and de])rive it of moisture. When the roots of neighbouring trees inter- 

 lace in the 20th year, the falling off in the hay crop is probably dvie to short- 

 age of water. If, however, instead of birches the grassland is planted with 

 deep-rooted alders, this phenomenon does not take place. Round about 

 the alders the vegetation is of better a])])earance than roimd the birches, 

 and is higher ; it extends right up to the tree trunks without any reduction 

 in height or change in colour, while arovmd the birches circles of weaker and 

 discoloured vegetation form which extend in the course of time. With re- 

 gard to the greater care required by the upkeej) of high forest alders as 

 compared with that demanded by birch trees, the desirability from the eco- 

 nomic point of view of planting grasslands with alder is brought out clearly : 

 with 220 alders per acre a good high crop ma}^ be maintained without 

 manuring and without any hindrance to the growth of the grass and the 

 use of the reaper. The trees may be replaced every 14 or 15 years without 

 injuring the grassland, by planting young trees 5 or 6 years old in the clear 

 spaces 7 years before felling the old ones. 



Anticipating the objection of insufficiency of sunlight on a piece of 

 grass land planted with trees, it is stated that though this objection may 

 be true for a wet climate it is not true for a dry climate, where excessive 

 sunshine results rather in burning the grass than promoting' the fojma- 

 tion of chlorophyll. 



Finally, stress is laid on the importance of the potassic and phosphatic 

 manure formed by the large quantities of dead leaves which a forest 

 17 to 22 years old is capable of yielding the elements of which are taken 

 from the subsoil. 



Although these observations do not constitute really strict scientific 

 experiments, they nevertheless enabled the writer to conclude with certainty 

 that grasslands planted with trees or wooded meadows will on the average 

 yield more hay than grassland without trees ; furthermore it supplies tim- 

 ber. It is, however, necessary, to repeat the experiments with cultivation 

 of the alder tree in regular lines to the number of 184 to 216 trees per acre 

 of grassland, doing the same with the birch and the oak, in order to as- 

 certain definitively whether the combination is desirable. 



976 - Moisture Content and Shrinkage of Forage and the Relation of these Factors to 

 the Accuracy of Experimental Data. — vonall h. n. and mc kkeRolanb, in Vnited 



States Dcpiiitmcnl ni Ai^iiculliirr, liullclin No. .^53, 37 pp. Washington, ]).C., March 13, 

 1 1)1 6. 



The variation in moisture content in field-cured forage often gives 

 rise to errors greater in amount than the differences in ^-ield between im- 

 I)roved varieties or different methods of culture. A study of the use of sam- 

 ples in correcting forage yields indicates the following results : 



i) Air-dried samples are a little less accurate than oven-dried 

 samples, but the difference is so small that the air drying of samples can be 

 relied upon for all practical purposes on correcting forage j'ields. 



2) Mtich greater extremes arc found in the sani])les of field-cured 



