•.

,:::·· '?able l• GroUll<\ Cover Tolerencea To "Preplant ln.;;l'l'Orated l!erl>1c1de Tabl~ 2. Orcwid .Cover 'l'Olerances to Po4tplsnt ·Herb1c1cle Treatments

Chemicals and Ratea* "Chemicals & Rates• Di 'l'riflural1n phenamid Di!lbilnamid Tr1nural.1n Growid Covers 10>4 5+1 l\+l . ~ L ..!L Diphenamid Sinnate 'l'r1f'.l.l!l""lin Ti-1nural1n S1maz1ne Siazine Al0X9ia tripl)ylla -- Ol'Ol.llld Covero 10 4 8 2 4 (Lippia). '!' '!' ~ Al&a1• tr1ffiYu~ (L1w1a) '!' T '!' T/I 'I' '!' ~ pilularil. '!' .'!' '1 S-'1' '1' s ·S - llacchar1a p1lular1e. 'I' T Ceraoti\1111 tomentos9 - 'I' T T 'I' 'I' '1' T '!' '1' s s cer.aatium •tomentoin.a 'I' 'I' 'I' 'I' '1' 'I' P!laO!lel'lllll !!!!! S-T"* S-'l"'* s s I 'I' s . Deleape,.... · Drosanthel!1Ulll W!!. T '1' T T T T' 'l' hiepidua :!'** S-'l' 3·'1' s s Dronsanthemwa h1ap1d1111 .2!!!.2!! splendens 'l' T 'I' '!'# T T 'I' s s -'l' '1"'* '1' '1' Redere , 9!.!!!!!!. splende~a '1' 'I' 'I' 'I' 'I' 'I' 'I' S-'l' canar1ena1e T '1"'* '1"'* s --rA!iierian ivy) Redera canar1enai& 'I' 'I' 'I' T 'I' T. T s . (AJ.serlan ivy) s Bedera helilc 'I' T -'I' 'I' ~lisii1v;y) Hedera helix ''l' 'l' 'I' T/I T 'I' 'I' s ( Eogl1SiiTvy) s ftymenocvclus luteolue 'l' 'I' $-'!' 8·'1' Hymenocyclua luteolua '1' 'I'' 'I' 'I' 'I' 'I' 'I' s s Osteospermum ~ '!'** '1"'* 'l' '1' Osteospermum ~ T 'I' 'I' 'I' 'l' 'I' 'I' s s Pelargonium ;peltatu111 'I' 'I' '1"'* 'I"'*· \'.', Pelargonium peljtuna 'I' 'I' '1' 'I' 'I' 'I' '1' '1' 'I'' ~ brevU'olium S·'I' S-'l' s s (Ivy geranium ~ guatemelense 'I' 'I' S•T S-'l' ~ brevitolium 'l'' 'I' 'l' T 'l' 'l' .. -, 'l' ,T ~minor lfM .,,. '1"'* '1"'* '1"'* ~ guatemalenee 'l' '1' 'I' 'I' 'I' 'I' 'l' 'l' ''l' 'l' '1' ~~ 'I' T/I 'I' '1' '1' •· S-'l' s-'!'. * Rates given are in Pounds ot act1,l&l ingredient per acre (i.I/A)

- Stunting * Rates given are 1n po1111da ot'actual ingredient l"'r acre (AI/A) # Chlorosis (early) f Chtoroa1a (early.) 1' • Tole~t at rat~ evaluated T • Tolerant at rate' evaluate4

s-~Syorptama of inJUJ7

S • sensttiv• to her:b1c1de at rate evaluated S ,. Sensitive to herbio1de at re.-:• evaluated .. '· . Preplazrt- treatments applied •• eaiula1fiable concentrate or vettable powder. Pa1tplarit treatments ·~pPued. as granules except atmaz1ne "hie~. Yas. a· ~ ,w:et't.bie llO"der ,:· for mutation. • · · Editor's note - After the above engraving was made, a11 error was. noted by co-author Clyde Elmore, In table 1, under. Ylnca minor, the 'Y' that Is shown should be a 'T' Instead,

WeeJ Control LJeJtJ-;J.n GROUND COVERS RELATtD

By C. L. Elmore, W. A. Humphrey and T. Kretehun* ·· 1 .•·

ROUND COVER PLANTINGS beau­ only on a limited scale, due to lack .. Aj_.field study.was. con~uct~ du~­ tify highways and many of knowledge and available selective ·mg ,1.967 at the University of· Cali· areas which are landscaped chemicals. Any reduc-: fornfa South Coast Field Stationin · throughout California, and .weeds tion in the cost of estalishing these Irvirle, to evaluate the effectiveness in these areas are not only objec­ ground cover areas can offer an of pre~emergence in se- ·. tionable, but costly. economic saving to' developers, .. lected commonly grown covers. Hand weeding always has been a landscape contractors and the gen· P,re-emergence herbicides are common methOd of weed control, eral public. those used to control weeds at ger· particularly in new plantings. How· · mination, i.e., prior to the time the ever, landscape contractors esti· *The authors are: C. L. Elmore, weed seedlings emerge from the . mate hand weeding may cost as Weed Control Specialist, University These herbicides are applied as close much as ten times that of chemical of California Agricultural Extension to planting time as possible for best weed control. Service; W. A. Humphrey, Farm weed control. Pre-emergence chemicals, which Advisor, Orange County, UCAES; In this field study a high level of might be used in many ground cover and Tom Kretchun, Principal Su- weed control was obtained with pre· plantings to reduce costs of weed perintendent of Cultivations, South emergence weed control chemicals. control, have so far been utilized Coast Field Station. .Several of the chemical treatments PAGE 16 PACIFIC COAST NURSERYMAN AND SUPPLY DEALER usea had no noticeable effect on application to activ~te the post­ fluralin (Table 2). Sirmate pro­ grQwth:c of the ground covers. Ap· treatments. vided adequate weed control plications made after and planting and Periodic evaluations were subse­ except for some early yellowing irrigated-in, were safer of than those quently made on tolerance of the foliage on some species, no effect applied before planting and .me­ ground covers to the herbicides (T: on growth chanically was observed. incorporated. When Sim­ tolerant; S-T: symptoms of injury; Weed control was azine was applied improved by post-plant, injury S: sensitive) and weed control ef­ incorporating the chemicals was observed into the on most species in this fectiveness. ( 0-10: weed control soil. Dihenamid was enhanced stu4y. more rating where 0: no control; 7: com­ than trifluralin (Table 3). However, G.round covers included in the mercially acceptable control; 10: as the data indicates, satisfactory trial were primarily broadleaved complete weed control, i.e., no weed control can be accomplished herbaceous plant species. The soil weeds). with post-plant applications when was a sandy loam with a physipal Tolerance Levels followed with sprinkler analysis of 57% sand, 24.7% $jlt, Post-plant applications of triflura­ and plant safety is improved. The 18.3% clay and 1.0% organic mat­ lin, diphenamid, and Sirmate, and principal weeds occurring in the ter. Two methods of treatment were the combination treatment of di­ trial were lambsquarters, several included: pre-plant incorporated phenamid plus trifluralin provided pigweed species, purslane and sow­ treatment with two chemicals, tri­ a high level of tolerance at the thistle. fluralin (Treflan and diphenamid rates used in this study (Table 1). Safely Used · (Dymid, Enide) . and post-plant Where Simazine was added in the Early post-plant applications of applications of trifluralin, diphena- combination treatments, a number some of the pre-emergence weed of the ground covers exhibited con· control chemicals can be used safely siderable injury (Table 1). On the in several of the frequently planted other hand, P. peltatum and the ground covers. Many of the com­ sedums showed remarkable toler­ mon annual weeds are controlled ance when Simazine was included with these herbicides. However, due in the treatments. Diphenamid in to the selective nature of these her­ general showed less injury with the bicides, certain weed species may pre-plant treatments than did tri- (Continued on page 46)

Table 3, Annual Weed Control Results Comparing Preplant Chemical Treatments CLYDE WESLEY A. on Ground Covers ELMORE HUMPHREY mid, Sirmate, combinations of tri­ Chemical and Treatment Rates- Weed Control# fluralin plus Simazine, diphenamid plus Simazine and trifluralin plus Preplant incorporated diphenamid. ·fhe higher rates of Diphenamid 8 diphenamid, trifluralin and Sirmate 8.5* were included primarily for toler­ Diphenamid 16 8.2 ance evaluations. The ground cov­ Trifluralin ers, the chemicals, application tim­ 2 10.0 ing, and rates of chemicals used are Trifluralin 4 10.0 given in Tables 1 through 3. .;1 Postplant Four of most plant species were planted into each 5' x 10' plot Diphenamid 5 6.5 and replicated four times. Three plants of Sedum brevifolium, S. Diphenamid 10 6.2 guatemalense and Pelargonium pel­ Sirma.te 4 8.2 tatum and two plants of Baccharis pilularis were planted into each Sirmate 8 9.2 plot. The pre-plant treatments were Trifluralin 2. 9.2 applied. B. pilularis and S. guate­ malense were planted July 6, 1967. Trifluralin 4 9.9 No mechanical incorporation of Diphenamid + Trifluralin 10 + 4 9.8 the post-plant treatments was used. However, sprinkler irrigation was Diphenamid + Simazine 5 + 1 9.5 utilized immediately after Trifluralin + Simazine 4 + l 10.0 Editor's Note-The trademarked chemicals mentioned in this article are products of: Treflan and Dymid, * One month follO\ling treatments Elanco Chemical Co.; Enide, Tuco - Rates are given in pounds ot actual ingredient Products; and Sirmate, Union per acre (AI/A) Carbide. # Rating scale-·O=no control, 10=1001> control

APRIL • 1968 PAGE 17 ~ r·~··cLAS~iFiED···-J PALMS 108 Wulfing Chosen To ·Manage YOU DIG - CASH & CARRY - MINIMUM ORDER $100.00 Col-Turf's Montclair Yard Chamaerops excelsa,. up to 3' ttunks...... 1.00 a fr, ..... '. ·······-········ Chamaerops exceba, over 3' trunks...... ;,.,3,00 a ft, Richard (Dick) Wulfing has been Wasingtonia robusra, to 4' trunks.... ;...... 1.01> a ft, (Continued from prereding page) Washingronia robusra, .over 4' trunks ...... 1.SO a ft, named yard manager of Cal-Turf's Cbamaerops bumilis, to 31h' ove.rall.... , ..... 1.00 a ft. Phoenix canariensis to 12' overall...... so a ft, ·new lawn center at 5135 W. Holt MAHONIA 101 Phoenix reclinata, to 10' overall...... 50 a ft, Blvd., in Montclair, Calif., accord­ Pines, Monrery, Canary Island to. 20• ...... 10.00 ea, MAHONIA Yucca (soft tlP, you cut) 3 to S'...... SO ea. ing to spokesmen for Cal-Turf, pro­ Ma.honia Aquifolium compacta, 21-1_" R.P.s. Cut• THE TROPICAL GARDEN ting grown. 3Sc ea. at 1000 rate, ¥.0.B. nursery. 3616 Mound Ave., Ventura, Calif. 93003 ducers of turfgtass stolons and sod Ready for early spring delivery 1968. CALL for appointment (805) 642-4024 DESCANSO NURSERIES - in Camarillo, Calif. P.O. Box 67, 6600 Beryl, Alta Loma, Cal.if, 91701 FIELD STOCK Washingtonia Robusta. 4-6 ft. overall The Montclair yard is keyed to Other slower growing_ varieties SAN DIEGO COUNTY serve the sod and stolon needs of LANDSCAPE MATERIAL 102 Write or telephone landscape R. W. DAWSON contractors and nursery­ SPECIMENS - MEDIUM SIZl! 2212 Andreo Ave. Tor.-ance, Calif. !10501 EXCELLENT OUAUTY men in the San Gabriel Valley and 1 GAL., 5 GALS.t..lS GALS.,_ & BOXES COCOS PLUMOSA - QUEEN PALM, Inland Empire areas, Cal-Turf of­ A PINTO iAG NUR:iERY 18' to 26'. excellent condition PAUL GAINES NURSERY INC, in our field, More Mesa Rd., Santa Barbara. YOU ficials report. ~ 836 North San Dimas Ave., San Dimas, Cal.if. 91775 DIG - CASH & CARRY - $50.00 ea. - one or (714) I.Ycoming 9·1511 one hundred. DEIGAARD NURSERIES, INC., 213·358·3285 Ground Cover Weed Control PALMS 108 RHODODENDRON 114 (Continued from page 17) A single plant of any of these SPECIMEN plants will CAPTURE THE SCENE : RHODODENDRONS not be controlled at selective rates. Huge-leaved palmetto palms. Container grown at Fort Bragg, No. Calif. 1 gals, An advantage Impressive clumps of bamboo style palms of Rhapls 2 gals, 5 gals, 7 gals and Specimens. New this of this type of chem­ humilis: Chamaedorea Schippit; costaricana and ical treatment is that a single treat­ erumpens. year, s gal.D'Es~,J{s8d~'f!itsERIES Huge African and Mexican cycads. P.O. Box 67 Alta Loma, Calif. 91701 ment may last several months, in Tall tree ferns. Frost-tolerant species of Fishtail Palms (Carvota) 1968 EDITION NOW READY contrast to hand weeding which may from the mountains of China and northern India A catalog of 48 pages devoted entirely to out - our own exclusive introductions. specialty. List of 211 hybrids including i.ron•clads, be required several times during the Also massive specimens of Platycerium fems . from new introductions, varieties suitable for Southern largest collection in California. climates, and those good for forcing. Rhododen• establishment period. Establishment CAUFORNIA JUNGLE drons for every purpose from America's leading is more rapid with weed competition 11977 San Vicente, West Los Angeles 90049 exclusive Rhododendron grower. GR 2-4763 VAN VEEN NURSERY reduced, and less damage occurs to 3128 S.E~ 43td Ave. Portland, Ore. 97206 PALMS - CITRUS TREES - ground covers with foot traffic re­ RARE CACTUS TREES 136 duced through the planted area. Palms field-grown. 100 lineal ft. or more Other techniques such as black Wash. Robusta, 10 to 18 ft. overall $2.00 per ft, CEDRUS DEODORA 'DifSCANSO DWARF' Wash. Filifera, 6 to 14 ft. overall 3.00 per ft. New clonal selection. Field and container tested polyethylene films or pre-plant Citrus trees well established in containers over 10 years. Bushy, compact. Dense needle fumigation treatments would be Oranges: Frost Navel - Valencia - Temple count, Pyramidal; Blue-Gray color, Parent 14' at , Pocan Honeyball - Orlando Tangelo - Temple. I 5 years. Finest for Living Xmas Trees, Patio more costly than the use of pre­ Tangerine: Fremont - Dancy - Clementine Pearl. Specs., Landscaping. Own toot trees in 2·gallon & S·galloo. emergence chemicals. These meth­ Ruby Red Grapefruit - Lisbon Lemon. DESCANSO NURSERIES These trees. fruit. this year for fall sales. 6600 Beryl St. ods are useful under some condi· In lots of ten or more - $10.00 each P.O. Box 67 ...... Alta Loma, Calif. 91701 Also many large trees, loaded wi.th fruit tions. CACTUS - Rare and Hard to Find Schottii - Devils fingers - Devils tree. YAMS 146 Cooperation extended by the Many large Plant Specimens fm landscaping, such University of California as shade trees-vines-yuccas-Bird of Paradise, YAM and SWEET POTATO PLANTS South Coast Sales. F.O.B. Nursery - Cash or Certified Check Nugget new heavy yielder· Field Station personnel and Harry We load you. Cash with all orders before digging. Also Hawaiian Sweets and Porto Rico Yams We are in Coachella Valley 3 miles south of the Y EDGAR BLACK Oda of Oda Nursery, Westminster, in Coachella, Calif. Stay on right lane of Hvvy. 86. 16596 El Rio Drive. Visalia, Calif. 93277 TRIPLE TWIN PAL'f NURSERY CO. Phone : (209) 594-4172 made this study possible. ~ t!heARl.ZONA CAMELBACK MOUNTAIN

Area Jn Scottsdale- the ''West's most Western Town" -12 mites northeast of downtown Phoenix. Arizona's newest and finest year around hotel. 180 luxurious rooms and suites-all with pri• vate sun deck, many have snackbar kitchens. Dining ~oom, .Cocktail lounge. Heated Swim• ming Pool. All sports and activities available. E~cellent Meeting I EUROPEAN PLAN facilities for groups I Write for Brochure up to 200. I ROBERT FOEHL, .Gen, Mgr. coltsdale. arizona PAGE 46 PACIFIC COAST NURSERYMAN AND GARDEN SUPPLY DEAI,ER L