Learning about our soil

Title

Creator

Cruz, Rosario I.

Language

English

Year

1958

Subject

Soils.

Soil science study and teaching.

Rights

In Copyright - Educational Use Permitted

Fulltext

Learning About Our Soil I. Gbjectives L To know th!lt one of the natural resources of our country is soil. 2. To learn how soils cliff er from one ano1 her; how to make a suitable soil mixture. 3. To understand what is meant by erosion; 'what causes erosion of soil. ' . 4. To find out what farming practices hurt the soil; what can be done to conserve the soil. 5. To realize the great importance of soil and be ready to _contribute, in whatever little way, to use our soil or conserve it wisely. II. What may be taken up in the study of the unit A. What soil means to every one l. keeps us alive·_ soil is a factor in the environment of living things 2. soil means foocl, clothes, shelter 3. soil means jobs - most of our industrial raw materials come from soil; many Filipinos are employed in factories which manufacture raw materials which came from the soil B. Kinds of soil - vary not only in chemical composition but in their physical properties, too. l. sandy soil - a. formed by the erosion of sandstones which ::ontain large quantities of silicon compounds b. not easily dissolved by water so it is not' good for plant life c. water is not retained well in this kjncl of soil; it is porous 2. clay soil a. generally rich in humus than sand .and contains more plant food JANUARY, 1958 By Rosario I. Cruz b. can support more plant life than sanely soil c. however, \\·heh dry, clay soil becomes hard and baked :~. loam soil a. best type of soil for 11lant growth b. is a mixture of clay and soil; holds water fair!~' 'Yell and does not become hard when dry c. kinds of loam soil ( 1) sandy loam - contains more sand than clay (2) clay loam - rnntains more clay than sand cl. loam soil is easy to plow and fit for seeding and cultivatio1: so is best for most agricultural crops C. How tn make a suitable soil mixture l. by preparing a compost heap in an out of the way corner of the yard a. consists of leaves, sod, garden refuse,, manure mixed with garden loam and left to decay b. pile leaves, garden refuse and soil. compactly in layers alternating with layers of manure c. pile should be kept moist· in order to help in the decay cl. mix materials thoroughly once a month for the bacteria to grow so· the rottening will be faster e. when well decayed, th~ mixture will be useful, for potting plants, flower beds, shrubs or top-dressing lawns · D. what eroston means; causes or factors of erosion of soil 1. term "~rosion" meai:s washing away of soil 2. cau::es of e1·osion of soil PAGE 39 a. heavy rains b. steepness of the land - the steeP,,er a slope is, the faster water rushes down the slope; the faster the water can rush along, the more it erodes the land c. harmful farming practices ( 1) clean· tillage - growing of crops in rows (Ex - corn) ; soil between rows is cultivated in order to prevent weeds from growing; this "clean" soil is left without covering; ·when the rain falls, water runs off rapidly instead of sinking into the ground (2) plowing up and down hillsides. If plowing is clone 'this way, channels in which \Yater flows 5Wiftly down the slope are made (3) cutting down trees on hillside (4) overgrazing creates erosion by destroying grass (5) overworking the soil E. Methods to c.:onserve soil 1. trees and grass must be planted to protect easily eroclecl land 2. coYer crops make a sod which protects the soil from washing (Examples - camote and peanuts) 3. crop rotation - planting of different crops in a particular field each yea1· for several years 4. contour farming - planting and cultivating crops in curved lines across a slope instead of in straight lines up and down the hill G. strip cropping - strips of cover crops are planted on the. contour between strips of new crops. The crowded cover crops catch the soil particles which are carried donwhill by the water from the clean tillage area above. G. Terracing F. How to keep the fertility of the soil - 1. topsoil should be kept 2. plant food can be returned to the soil in t~e form of fertilizers 3. crops can be rotated 4. legumes which supply nitrogen to the soil can be grown 5. plowing uncle1· the unused parts of crops such as the stalks of corn PAGE 40 III. Projects and Problems for Discussion A. Projects to do 1. Experiment with different. kinds of soil Get 3 flower pots; fill one with sand, one with loam and one with clay. Plant two or three different kinds of seeds in each. Keep each pot under exactly the same conditions as the others, giving the same quantity of water. Note the pot in which the seeds sprout first; note in which pot the soil seems to dry quickest and in which the plants seem to grow best. ., 2. Make clay models of farms showing the various methods of conserving soil. 3. Draw a poster to show the need for soil conservation. 1 4. Go around y<;>ur locality. Talk with some of the farmers. Ask them how they conserve the soil; how they preserve the fertility of their soil. 5. Visit the school garden. Observe ho\',· fertilizers are used and the effect upon plants. 6. Write to the Department of Agriculture and Natural Resources to ask for any material about our soil and how it is being conserved .. B. Problems for discussion 1. Discu.:;s: ' a. Why conservation is everybody's business b. Sick land makes sick people c. The things you eat and use which can be traced to the soil cl. How soil has helped man all thi·ough the centuries of years e. How man has improved the fertility of the soil 2. H:we a little debate on this topic: Farmers have a right to do what they wanted to do with the land. 3. Research and report on countries which have been farmed for centuries yet the soil remains fertile. Discuss the report afterwards especially emphasizing about the methods of farming in those countries. REFERENCES: 1. Craig, Gerald S. S{cence for the Elementary School Teacher; G.inn and Co. 1957 2. Rhyne, Conway L. and Lory, Ellsworth E. Conservation of Natural Resources: Charles Merril Co. 1957 3. Partridge, J. A. Natural Science Thl'ough the Seasons; the MacMillan Co. 1947 . ' 4. Science Source Book (prepared by Evansville Public Schools, 1953) THE PHILIPPINE EDUCATOR

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