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HomeMy WebLinkAboutP-49-78 CORPORATION OF THE TOWN OF NEWCASTLE PLANNING DEPARTMENT TELEPHONE 263-2231 -- HAMPTON, ONTARIO, LOB IJO TO: V.11.0, 0,f -%110, Development Committee 1',I7 ), XUATICY: Repovt on Progomration Act WAY06"Ki On ill 29, 1978, the Plonning W Development Convittee, Dr,nno(7,, the followinT resolution QPD-261-78, "That the verbal report be received, Pt10 the further P. by-1 the Tognoil Prenorvntioi lc-' � "n(l flr ")lc' by-laws from othev PIRcon for R review by the 021 lia' 2"', 1979, the Ministry of Aarjoylti.ron arJ lloo,� IGO the TOXn Of 70=S e attached corrosponklonce.. VIii-.i ..nc__`, on.tei t",-,t tPe Jlli,nistry do not have a noUl by-law 1Ln6er the AV nrR am(,' not Male Of 02?-- 1-lunicip alit y which has Dasse? a by-law un&r thr, ""('t. Yhe ToWn of Newcastle would rnmvxentl,, be tho �.n On-,;a;'io -to nasn a, b-i.r_j,3:,e! uLn I oi) _�oe '0 dnr C..Ie Twx. Ac 3- jpcal lituntion Staff of We 71anning Nepar• ment havo conn"Ited wAth th, local. i(' :?npresentative and have been ROW nod PH An Aq not of an-'- --r)-roblemn preaently annociated with the 7n-ovrj of W_ poll in the Vim Of Nowmitlo. cultural RennonartAtAve w _en nej a Wilin-mesn to helo with tho "7e7)2ration of R b7-lau7 bl't not fxdliar with the Ontolls 01 the >7002ion. Tf Vle, Tm:n of 'Towcastle -IT-onenmn to OTaft a W-Iry aloe, Ov �OImoil Act, it will b 1 rha:-, "i7 _71C1 Wq' NO all of the other '.TmrliciT)al'itiop in War in, 7e bKOVC: thorefone, thi--v"; if t1le To-vrfi of Newcastle pronnedn to Monem., larABlation in this fiela, it shout hava the boreVA V W40 mymt advAnn. In this easel it is mcconmended that the 11PPOny, e be authorized to obtain the servic'e-i of -, - MANY, or other coi-mel, if the Town Aolinitnn ''..ac in- sufficient Ove to deal with tbin natter at prenent,P& Ono the ,c-n,.--c(,:7 o:' a, consultant aCTonomint. / IV711 * Creorcr- Tolm I V E D Ontario JUN 2 1978 Ministry of T0\.k,fN" 01" IJ,,WII/-,I,\STL4-lJI965-9433 Legislative Buildings Agriculture Queen's Park and Food Toronto Ontario May 25, 1978 Mr. George Howden Planning Department Town of Newcastle HAMPTON, Ontario Dear Mr. Howden: I have enclosed, for your information, a copy of an article entitled "Topsoil Removal - Mineral Soils: Effects and Re- comaw-ndations". You may find this information of use to you in terms of possible effects of topsoil stripping and rehabilitation techniques. Mr. Spencer may have mentioned that we have not drafted a model by-law. Such a by-law cannot take into account local problems to be dealt with. I am not aware of any munici- pality that has to date passed a by-law under the Act. Yours very truly, Don W. Gallagher Manager Land Management & Project Review Food Land Development Branch Ilg Encl. i TOPSOIL REMOVAL-MINERAL SOILS: EFFECTS AND RECOMMENDATIONS Ontario Ministry of Agriculture and Food Food Land Development Branch INTRODUCTION: Soils of Ontario are extremely variable in nature. This variability is reflected in the diversified land-use, soil management and productivity found throughout the province. For all their dissimilarities, these soils have a common characteristic. The surface layer, or topsoil , is the most vital part of each soil profile. This upper layer of soil is the principal feeding zone of the plants which provide food for human or livestock consumption, fiber for clothing and timber for shelter. 300 to 1000 years are required under favourable conditions to build a single inch of topsoil by natural processes. Although this formation can be speeded up by the actions of man, it will be time consuming and difficult at best to restore the soil to full productivity after topsoil is removed. Before any site is stripped of topsoil the repercussions must be carefully considered and a plan of action determined to rehabilitate the soil for the growth of plants. i I 2 This report is presented in 3 sections: Section A. Soil Problems Associated with Removal of Topsoil This section outlines the types of problems that may occur when the productive topsoil layer is removed. Section B. Topsoil Removal Methods & Site Selection This section outlines methods of topsoil removal as we'll as the selection of sites which will result in the fewest environmental and rehabilitation problems . Section C. Rehabilitation Procedures This section indicates rehabilitation techniques that should be used to restore productivity to the site and help to control erosion. A. SOIL PROBLEMS ASSOCIATED WITH REMOVAL OF TOPSOIL When topsoil is removed from land the subsoil becomes the surface layer of the soil . A number of problems may occur as a result of removing the productive topsoil layer. 1 . Erosion The most immediate concern subsequent to topsoil removal is erosion of the subsoil by water and/or wind. Topsoil is not as subject to erosion as subsoil for a variety of reasons. a) organic matter in the topsoil layer improves the soil structure by increasing the amount of pore space and permeability of the soil . More water from rainfall therefore enters the soil and run-off is reduced. b) vegetation growing in topsoil reduces erosion by helping to form water stable aggregates and by acting as an anchor for the soil . Due to the lack of water stable aggregates and low permeability of subsoil , runoff is accelerated and therefore soil erosion. This problem is generally worse with clay soils. As sandier soils are generally more permeable with less structural change at depth than clay soils, more water enters sandy soils and runoff is reduced. Sandy soils are, however, more susceptible to wind erosion than clay soils. 2. Reduced Soil Fertility Topsoil is largely responsible for producing most crops. Removal of topsoil often exposes dense subsoils which are infertile and poorly suited physically for growing crops. The causes of reduced fertility in land stripped of topsoil are: a) loss of organic matter with its beneficial effect on the soil . b) impaired structural efficiency c) reduced availability of moisture d) lack of essential plant nutrients In addition microflora and fauna are lost with the topsoil . These microbiological organisms enhance soil conditioning, aid in the supply and cycling of nutrients and add organic matter. Soil productivity may drop in excess of 80% when topsoil is removed. Yields on fertilized subsoil may be 40 to 50% lower than on unfertilized topsoil indicating that reduction in fertility is not the sole factor involved in productivity decline and fertilization alone will not restore productivity to its former levels. . . ./4 - 4 - 3. Soil Compaction When subsoil is subjected to the weight of heavy earth moving equipment, soil compaction can occur. Compaction of the soil reduces the amount of air and water in the soil . In addition, compacted subsoils frequently develop a hard surface layer upon drying. These factors result in reduction of plant growth due to: a) lack of moisture in the soil b) gemination of seed may be reduced c) emergence of seedlings is reduced d) root elongation is reduced e) due to increased surface runoff erosion increases Soils are most easily compacted in a wet state. In general , soils that are uniform in particle size are more susceptible to compaction with clay soils being the most susceptible. B. TOPSOIL REMOVAL METHODS & SITE SELECTION 1 . The detrimental effects of removing topsoil can be reduced if only a portion of the topsoil is removed. In this way many of the beneficial aspects of topsoil will be present and rehabilitation will be faster and more complete. 2. Erosion and soil compaction can be reduced if sites are carefully selected. Practices that will help reduce these factors are: a) select sites which are on relatively level land - 5 - b) medium textured soils are less susceptible to damage as water normally enters these soils rapidly and in addition they resist compaction, puddling and slaking. c) Topsoil should only be removed during dry periods of the year. Subsoils compact more readily when wet and high rainfall increases erosion. d) the use of heavy equipment should be avoided wherever possible. Light equipment or floatation equipment should be used in order to reduce soil compaction. C. REHABILITATION PROCEDURES 1 . If only a portion of the topsoil has been removed or if some topsoil is returned to the land rehabilitation will be accomplished in less time and with lower inputs of fertility, organic matter and tillage. 2. Cover the exposed subsoil as quickly as possible to reduce erosion. Any method that reduces the velocity or amount of flow of wind and water over the soil will reduce erosion. Straw mulches, artificial mulches or brush cover will help to reduce erosion until vegetation is re-established. 3. Establish a cover of vegetation, Grasses and legumes can be established on subsoils and provide adequate control of wind and water erosion. This minimum treatment will not however result in agriculturally satisfactory yields. Any attempt to apply intensive cropping practices i 6 - would likely result in a reduction in plant stand and therefore wind and water erosion control . Productivity will be restored in less time and to higher levels if the site is properly prepared before planting takes place. a) Reduce soil compaction. Where compaction has occurred , it may be necessary to alleviate this condition before vegetation can be established. Subsoiling, ripping and/or chisel ploughing are effective methods of reducing compaction. These procedures break up impermeable layers, improve structure and drainage but must be performed only when the soil is dry. b} Plant grass or forage legumes, These species are preferred as they control erosion, improve soil structure and permeability, and supply nutrients. Legume species such as alfalfa, birds-foot trefoil , or clovers are preferable as they supply nitrogen to the soil and improve structure. Legumes may however, be more difficult to establish than grass. c} Re-establish soil fertility. The soil should be analyzed to determine its fertility requirements* and fertilized according to recommended levels. If possible organic fertilizers such as livestock or poultry manure should be spread on the soil and worked in. These materials supply organic matter, improve soil structure , and reintroduce soil bacteria and nutrients. *Information on soil sampling procedures as well as sample bags are available from county offices of the Ministry of Agriculture & Food. - 7 - A soil test will also indicate if there is a requirement for lime to increase the pH of the soil . Information on planting and tillage procedures, fertilization methods and suitability of various crop species and varieties is available from the local county office of the Ontario Ministry of Agriculture and Food. SUMMARY: Sites must be carefully selected to reduce soil erosion and hasten rehabilitation prior to the removal of topsoil . Relatively flats sites of medium-textured soil are preferable. Vegetation must be established as quickly as possible in order to control erosion and return the site to some measure of productivity. Soil compaction may need to be alleviated and the site fertilized preferably with organic materials according to soil test recommendations. I i i