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Home My WebLink AboutCT 74-21; CARLSBAD OAKS BUSINESS PARK; SLOPE SOILS SAMPLED; 1987-07-06T ;. fht RECEIVED JUL -'7 197 Santa Ma Office- SOIL. AND PLANT LABORATORY, INC. Lab lb • 4391 MimOw 01. The C.iIoini Au0IIo% 01 AQilCl* 0(110($$' •• PcD 1549 India Street San Diego, CA 92301 Attn: Barney Matsumoto CARLSBAD aAKS. BUSINESS CENPER - SLOPE SOILS 'SAMPLED 6-29-87 appear to be priirarily sandy loam in texture... The- soil data indicate that soil reaction is.. strongly alkaline with line content medium .: Salinity is satisfactorily low and boron is also low and. poses. no hazard to plant growth. Available nitrogen is very low with phosphorus also low. Potassium is near optimum and calcium and magnesium are both well supplied. Inroved growth would be expected with the application of a nitrogen and phosphorus-containing fertilizer. Miiniuxn phosphate (16-20-0) -.should be broadcast, over dry slope areas at a rate of 5 pound per 1,000 square feet and followed with a normal irrigation. At 30-day intervals after the first fertilizer application, 16-6-8 should be broadcast. at a rate of 6 pounds per, 1,000 square feet of dry slope area. These fertilizations should also be followed by a normal irriga-tion. Location 2 Location 2. represents a srrall streetscape slope which-.had-been-hand planted. The soil at this location consists of a medium brown sandy, loam soil and localized area of a dark grey soil high in silt content. The poorest plant growth was noted in the areas consisting of. this dark grey soil. Soil reaction in this area is strongly, acid with salinity (ECe) at a level where sensitive plant material would be adversely affected. There is a strong possibility that,the salinity is considerably higher in the dark grey localized areas.. Boron in this area. poses no:hazard. to plant growth and: sodium. is well balanced' by. calciuiw and magnesium., ... Available, nitrogen and phosphorus' are both- low with potàssiüm moderatel low, Calcium and magnesium are both high... -. ......................................................................... flF n . ... C..... A.. IIiI.I. fl1WI 1_7A, rTlA1 I .tJ_ IJ%I I II 1• IJCIuIC nllc_ .IIIJuI iS ......,, J •,, _I w.J,a. Telex Numbur. 5101000505 ANSBltSo&lP1antSA . . Box 153. Santa data. Calilomia 95052-0153(408) 721-0330: i 7) P.O. Box 1648. Belk*vue1 Waaalng(on 98009-1648(206)746-6665 SOIL..AND PLANT LABORATORY ,INC. Member of The California Assoclatloti of AgIsCuttuisi Lsbo.alo,ies. Page 2.. PCD July 6, 1987 4.. Due to the variable nature of the soil in this area, uniform growth will be difficult. Salt-tolerant plant material should be selected for this area. The fertilizer program outlined, for location 1 cam also be used in this area. If localized areas are to be replanted, calcium carbonate lime or ground oyster shell. lime should be uniformly broadcast in there-landscape areas at a rate of. 250 pounds per 1,000 square feet. The lime and artiw.nium phosphate should be scratched. into the soil surface to the waxiirum depth possible prior to replanting.. Location 3• This location represents a slope betweem two building pads.: A. soil sanple was taken primarily: from. the. dark grey soil which. makes: up the lower portion of the slope.. This soil has::a high. silt andl clay. content.. Soil reaction is extremely acid_ and salinity, would restrict the growth of most plant material. The boron content would restrict the growth of sensitive ornamentals. The SAR. vaIue: indicatesthat.sodiUm. is well:': ba1anced' by.:calciurn" and' magnesium although there appears to- be: an.. excess: ofiinagnesiuin;.in' this: soil.. Although of little.. inportance at', this location,.. available. nitrogen.', is. low with phos- phorus and potassium also low. Due to the adverse physical and, chemical properties of the soil in this area, it will be very difficult to establish plant material on this slope. Limited success has been achieved in' similar soils by hand planting extremely salt- tolerant material such a 1-gallon acacia redolens. If planting is atteipted in this area, the following amendments should be uniformly broadcast and scratched into the. surface to. the. niaxijruin depth. possible.. SOIL AND PLANT LABORATORY, INC. Member of Th. California Association of Agriculiuisl Laboratories Page 3 co July 7, 1987 This large slope area consists prinerily of .a fine sand which has been com- pacted in many areas. Soil reaction is moderately alkaline and salinity is satisfactorily low. Again, boron.-popes-no hazard to plant growth and sodium is well balanced by calcium and magnesium. Available nitrogen and phosphorus are both low with.. potassium low optimum. Calcium and magnesium are well supplied. Although nitrogen and phosphorus fertility levels are low in this area, the primary cause of poor plant establishnent appears to be. due to poor physical conditions. Plant: growth appears satisfactory in areas where root and water penetration are not limited by compaction... Hand: planting these conc?acted and semi-cemented areas will probably be more effective than. re-hydroseeding. Fertility levels in this area could be inproved by following the fertilizer maintenance program outlined, for location 1. Location 5 . This sanpie represents a large slope area east of location. 4. Soil conditions are quite variable in this area and some of: the. conpacted, cemented conditions found in location .4 exist here also. Soil reaction. in this area is near-neutral in reaction with, lime content medium. The salinity level in this area would restrict growth of most plant material.. Although sodium is at present in appreciable quantities, it is well balanced by calcium and magnesium. Again, boron poses no hazard to plant growth. Available, nutrient levels are. similar .to location 4 with nitrogen and phosphorus being low and potassium slightly lower than optinum. Some plant growth in this area appeared. satisfactory and it appears that soil chemistry may vary widely within, this area.. In. areas that have not grown well after hydroseeding, plants. showing a high degree of salt tolerance should be used when. replanting. Fertilizer, levels can be inproved in this area by again following the fertilizer maintenance program. outlined, for location 1. Due to the highly variable nature of the soils,at this cut and fill project, it is very likely that some localized areas of high salts have not been identified by this sanpling visit. The undersigned is routinely in the Carlsbad area during the last week of each month, should further soil sampling of this site be needed. If we can. be of. further'assistance, please call.. W.L I/p I — WILLIM DARLflG'ION . . - End: Salt tolerance list and site plan. WD:nw P.O. Box 11744. Santa Ana, California 92711-1744/(74) - ot ad CPat abokatok, On.P.O. Box 153, Santa Clara, California 95052-0153/(408) 727-0336 POD SOIL FEIILITf AND AGRICULTURAL SUITABILITY Santa Ana Office • 1549 India Street (A04) Lab. No. 4391 San Diego, CA 92101 July 6, 1987 Carlsbad Oaks Business: Center 'soil Saiples taken 6-29-87 Saturation Extract Values_____ Sam Half ____Parts Per Million Dry Soil I Ca Mg Na K B SAk QUAL pie Sat. I t03-N NH4-N PO4-P K Ca Mg I pH IECe Me/i Me/i Me/i Me/i PPM I LIME 1-. 1 22 1 4 11 130 8100 694 8.0 1.5 4.5 1.9 8.8 0.3 0.17 4.9 MED 2 23 0 7 6 100 10020 61 4.7 3.8 28.7 11.2 10.9 0.4 0.34. 2.4LcM ' 3 26 1 9 4 70 70832 2.8 11.9 17.8 125.0 5.7 0.3 1.23 0.7 11W 4 21 3 5. 5 130 6780 756 7.7 . 1.3 2.5 1.2 9.5 6.2 .0.20 7,0:.MED 5 15 2 4 8 80 5500 425 7.2 10.4 61.0 15.5 31.5 0.5 0.19 5.1 MED Half Saturation %-approx field iroisture capacity. Salinity = ECe (rr1xs/cm at 25 degrees C.) SAR - Sodium Adsorption Patio. Location 1 Location 2 Location 3 Location 4 Locat4 5