EFFECTS OF ARASAN AND R-55 ON GERMINATION OF BLACK SPRUCE AND JACK PINE SEEDS

Transcription

1 EFFECTS OF ARASAN AND R-55 ON GERMINATION OF BLACK SPRUCE AND JACK PINE SEEDS J.W. FRASER GREAT LAKES FOREST RESEARCH CENTRE SAULT STE. MARIE, ONTARIO REPORT O-X-32 CANADIAN FORESTRY SERVICE DEAPRTMENT OF THE ENVIRONMENT SEPTEMBER 198 Copies of this report my be obtined from: Informtion Office Gret Lkes Forest Reserch Centre Cndin Forestry Service Deprtment of the Environment Box 49 Sult Ste. Mrie, Ontrio PSA SM?

2 ABSTRACT Experiments to determine the effce or two reputed rodentrepellent cotings, Arsn nd R-55, on germintion of blck spruce (Fics rnrinc. [Mill.] 3.S.?.) nd jck pine (Finns henksi-n Lmb.) seeds re documented nd evluted. Neither coting hd ny pprecible dverse effect on germintion of blck spruce seeds, except t low temperture (IOC) where R-55 depressed germintion slightly below tht from untreted seeds. Coting jck pine seeds with Arsn invribly depressed germintion but pprecibly 5 only t low temperture (IOC). Length of storge hd no prcticl effect on germintion of blck spruce coted with either Arsn or R-55, but did depress germintion of Arsn-coted jck pine seeds t low temperture (IOC). RESUME Documenttion et evlution d'experiences en vue de determiner les effets de deux enrobges reputes pour repousser les rongeurs, Arsn et R-55, sur l germintion des grines d'epinette noire (Hs mrin [Mill.] B.S.P.) et de Pin gris (Pinus bnksin Lmb.). Aucun des deux enrobges n' eu d'effet dverse pprecible sur l germintion des grines d'epinette noire, suf I bsse temperture (1 C) ou l germintion des grines tritees u R-55 etit legerement inferieure celle des grines non tritees. L'enrobge des grines de Pin gris vec Arsn invriblement diminue l germintion mis de fcon pprecible bsse temperture (1 C) seulement. L duree d'entreposge n' eu ucune influence prtique sur l germintion des grines d'fpinette noire enrobees vec Arsn ou R-55, mis diminue l germintion des grines de Pin gris enrobees d'arsn bsse temce^ture (1 C).

3 ACKNOWLEDGMENTS I m indebted to former forest reserch technicin, J.M. Shoup, for his ssistnce with the Arsn nd R-55 experiments nd to forest reserch technicin, M.J. Adms, who conducted the supplementry experi ment with Ltex 636 nd prepred the numerous histogrms in this report. I m lso indebted to A. Rdvnyi, reserch scientist, Cndin Wildlife Service, for pplying the R-55 tretments, nd to the Ontrio Ministry of Nturl Resources for pplying the Arsn tretment.

4 TABLE OF CONTENTS Pge INTRODUCTION L METHODS AND MATERIALS, Arsn Tests 9 RESULTS R-S5 Tests 2 Arsn Tests (Blck Spruce) 3 Arsn Tests (Jck Pine)... 6 R-S5 Tests (Blck Spruce) 6 DISCUSSION AND CONCLUSIONS 13 LITERATURE CITED. ' ' * * * 14 APPENDICES

5 INTRODUCTION This report dels with the influence of two reputed rodentrepellent seed cotings, Arsn, nd R-55, on germintion1 of blck spruce (Pioe mrin [Mill.] B.S.P.) seeds. It lso dels with the influence of the Arsn coting on germintion of jck pine (Pinus bnksin Lmb.) seeds. The report is bsed on series of germintion tests in constnt-temperture incubtors over period of severl yers, nd documents the germintion response of coted nd of untreted seeds to different tempertures in reltion to how long the coted seeds were stored before they were tested. For the rtionle behind the experiments reported here nd for comprehensive review of literture on these nd other seed tretments reders re referred to Frser's (1974) pper t the Timmins symposium on direct seeding. Preliminry results presented then were updted, s ws the literture review, t the Thunder By symposium on blck spruce (Frser 1975). The end results of these experiments, since completed, re documented in this report. When these trils were initited there ws widespred con troversy concerning 1) the need for rodent-repellent cotings on blck spruce nd jck pine seeds sown on borel forest cutovers, 2) the efficcy of the estblished Arsn nd recently developed R-55 cotings (Rdvnyi 197) s rodent repellents, nd 3) the dverse effect, if ny, of either coting on germintion of blck spruce. In ny event, by the time the experiments initited to help resolve the third of these controversies were completed, Phillips Petroleum hd discontinued mnufcturing R-55, Arsn 42S ws no longer vilble, nd Dow Chemicl hd stopped producing ltex 512R, the binder in the Arsn coting. Hence, the results of these prticulr experi ments now hve no prcticl significnce whtever. However, ltex, the "binder" used in both these cotings, will probbly continue to be'used s such (in one form or nother) unless or until there is documented evidence tht there is no need for lubricnts such s luminum flkes or grphite to fcilitte pssge of blck spruce or jck pine seeds through mechnicl seeders. Also, opertionl direct seedings using Arsn-coted seeds re still being ssessed nd the influence of Arsn on germintion should be considered in evluting the results. For these resons, if for no others, the results of these experiments wrrnt documenttion. In this report germintion refers only to germintion under specified conditions in growth chmbers or incubtors, s opposed to field germintion.

6 - 2 - METHODS AND MATERIALS The Ontrio Ministry of Nturl Resources provided the seeds used in these tests nd lso pplied the Arsn cotings (Arsn + ltex + luminum) (Appendix I). The Cndin Wildlife-Service provided nd pplied the R-55 cotings (Appendix I). Arsn Tests Germintion of coted nd untreted (control) seeds of both species, stored in seled continers t 2C-4C, ws tested in controlledtemperture cbinets t IOC, 21C nd 32C (constnt tempertures), 2, 4, 8, 1, 12, 14 nd 18 months fter the cotings were pplied.2 The scheduled 2-month-intervl storge tests were interrupted, indvertently, t 6 nd 16 months. For ech of the storge-period tests, seeds were sown onto the surfce of sturted, short-grin, blck germintion pper over sturted Kimpk3 in sterile petri dishes. There were four dishes (replictes) of 1 seeds ech for ech tretment (control, coted) per temperture. The seeded dishes were covered nd llocted rndomly to temperture tretments. Moisture of the germintion medium ws mintined by dding mesured mounts of distilled wter if there ws ny indiction of drying. Germintion ws tllied dily for 28 dys: seeds were tllied s germinnts when rdicles were t lest 2 mm long, or longer thn the long dimensions of the seeds. R-55 Tests Germintion tests of five different R-55 cotings on blck spruce seeds prlleled the Arsn tests in ll other respects, i.e., the sme three tempertures nd the sme eight storge periods. Subsequently, germintion of untreted nd coted seeds stored for pproximtely 4 yers (47 months) nd for 6 yers ws tested t 21C. Shortge of seed precluded testing t IOC nd 32C. All dt from these tests were nlyzed by the Chi-squre method. Tretment mens, stndrd devitions nd coefficients o vrition bsed on cumultive germintion dt were clculted for individul storge tretments nd for ll storges combined 7, 14, 21 nd 28 dys fter seeding. 2Shortge of seed precluded the 14- nd 18-month tests with jck pine. ^Mention of compnies nd/or products in this report does not constitute endorsement of either by the Gret Lkes Forest Reserch Centre.

7 - 3 - RESULTS Arsn Tests (Blck Spntce) For ll storge periods combined (Fig. 1} it is evident tht, lthough gemintion t 21C ws better thn t 32C nd t IOC, in tht order, throughout the test, i.e., t weekly intervls, there were no pprecible differences mong the responses from coted nd untreted seeds t ny temperture t ny time. The coefficients of vrition (Appendix II, Tble Al) confirm this nd indicte tht germintion occurred uniformly t 21C, less so t 32C nd lest so t IOC. Although the differences in germintion from coted nd from untreted seeds re miniml, germintion t 21C obviously ws not only better thn t 32C nd IOC, but ws effectively complete only one week fter seeding. At 32C, lthough germintion incresed with time, the increse ws miniml fter the second week, wheres, lthough there ws no germintion t IOC until the third week, it ws t lest s good s it ws t 32C by the end of the test. Do these temperture/germintion responses of coted nd untreted seeds vry pprecibly with the length of time seeds re stored prior to testing? As cumultive percent germintion obviously must increse with time until germintion is complete, tretments mong which there is no significnt difference hve been verged to simplify grphicl present tion of the dt (Fig. 2). For exmple, for the 1-ronth storge test with untreted seeds t 32C (Appendix II, Tble A2), germintion t 7, 14, 21 nd 28 dys ws 67, 92, 94 nd 95, respectively. Since there ws no sttisticlly significnt difference mong 92%, 94% nd 95%, the men vlue, 94%, is plotted for 14, 21 nd 28 dys in Figure 2. It is obvious (Fig. 2) tht t 21C, length of storge hd no effect on resultnt germintion of either untreted or coted seeds. It is eqully obvious tht length o storge hd no pprecible effect on the pttern reveled when ll storge tretments were combined, i.e., more nd fster germintion t 21C thn t 32C or t IOC. No supportble hypothesis hs been dvnced for the bnormlly poor germintion response from both untreted nd freshly coted seeds ( months' storge) t IOC nd 32C reltive to the response t 21C in the sme test nd to those t the sme tempertures s storge periods incresed. Even if llownce is mde for the bove-mentioned nomlous response from untreted nd freshly coted seeds ( months' storge) t IOC nd 32C, Figure 2, while confirming tht germintion ws better nd fster t 21C thn t 32C nd IOC, clerly illustrtes the lck of ny dverse effect of storge on coted seeds.

8 - 4 - BLACK SPRUCE 1 _ 9 _ z SO _ O h ;o_ I 6 _ 5- >" 4, z LLJ O 3. cc LJJ cl _ C [5F] 21C L7FJ 32C [9F] CONTROL ARASAN Figure 1. Cumultive percent germintion of blck spruce seeds (ll storge periods combined) 7, 14, 21 nd 28 dys fter seeding t IOC, 21C nd 32C.

9 BLACK SPRUCE ' is 18 UNTREATED AHASAN UNTREATED ARA5A.N 1C 33C Figure 2. Men cumultive percent germintion of blck spruce seeds bv temperture nd seed tretment 7, 14, 21 nd 28 dys fter ' sowing seeds scored for, 2, 4, 8, 1, 12, 14 nd 18 months

10 - 6 - Artisn Tests (Jck Pine) For ll storge periods combined it is evident from Figure 3 tht jck pine germintion, like blck spruce germintion (cf. Fig. 1), ws consistently better t 21C thn it ws t 32C nd t IOC throughout the test, but unlike blck spruce germintion, it ws invribly better from untreted (control) seeds thn it ws from coted seeds. As indicted by the coefficients of vrition (Tble A3), jck pine germintion ws more uniform t 21C thn t 32C nd IOC (similr to blck spruce). Unlike blck spruce germintion, it ws more uniform from untreted thn from coted seeds even t the best germintion temperture, i.e., 21C. For jck pine somewht different pttern emerged thn for blck spruce (cf. Fig. 1). Although germintion of jck pine seeds t IOC ws delyed until the third week, s ws the cse with blck spruce seeds, germintion from coted seeds ws consistently poorer thn from untreted seeds. Given time, i.e., 28 dys, untreted seeds germinted lmost s well t IOC nd t 32C but coted seeds did not. Germintion of jck pine seeds t 32C begn s soon s germintion of blck spruce t tht temperture, but unlike blck spruce germintion, it ws complete by the seventh dy. However, it ws considerbly poorer reltive to germintion t 21C thn ws the cse with blck spruce, nd unlike blck spruce germintion, it ws consistently poorer from coted thn from untreted seeds. Coefficients of vrition (Tble A3) indicte more uniform germintion from untreted seeds (except perhps t 32C) thn from coted seeds nd lso more uniform germintion t 21C thn t either IOC or 32C, regrdless of seed tretment. The length of time seeds were stored hd little, if ny, effect on the germintion/temperture responses of either untreted or coted seeds (Fig. 4, Tble A4). Only t IOC, where the pprently incresing but irregulr, depressnt effect of storge on germintion ws more pronounced on coted thn on untreted seeds, did storge pper to hve ny effect on the germintion response of untreted or of coted seeds. R-SS Tests (Blck Spruce) For ll storge periods combined (Fig. 5) the pttern of germintion response is quite similr to tht estblished for Arsncoted blck spruce, i.e., consistently better germintion t 21C thn t 32C nd IOC, in tht order, for both untreted nd coted seeds. In this instnce, however, lthough coted seeds never germinted s well s untreted seeds t 21C or IOC, there ws no pprecible difference in germintion from coted versus untreted seeds t 32C (except for tretments 2 nd 3 where germintion ws inexplicbly low). Coefficients of vrition (Tble A5) indicte tht here, s with Arsncoted seeds, germintion occurred more uniformly t 21C thn t 32C nd t IOC, nd tht untreted seeds usully germinted more uniformly thn coted seeds.

11 - 7 - JACK PINE C 32C CONTROL m ARASAN Figure 3. Cumultive percent germintion of jck oine seeds Cll storge

12 _^^ JACK PINE 'CO _ ICQ ^ 2 D O 1, y- Z UJ O in c 7 u 21 SB UNTREATED ARASAN UNTREATED ARASAN UNTREATED 7 U ARASAN 1C 32Q Fisure 4. Men cumultive percent germintion of jck pine seeds by temperture nd seed trecment 7, 14, 21 nd 28 dys fte sowing seeds stored for, 2, b> 8, 1 nd 12 months.

13 9q c H ID PERCENT GERMINATION

14 - 1 - If llownce is mde for the different mount of germintion t 21C, 32C nd IOC, in tht order, germintion begn erlier t 21C nd t 32C (7 dys) thn t IOC (14+ dys) nd ws effectively complete sooner (14 dys) t 21C nd 32C thn t IOC (28 dys). Note tht these ptterns were mintined for coted s well s for untreted seeds. If one considers the effects of storge (Fig. 6, Tble A6), the lmost complete lck of germintion from freshly coted seeds t IOC nd t 32C suggests possible initilly toxic effect of R-55 which is not opertive t 21C. However, this hypothesis is untenble s germintion ws lmost eqully non-existent from untreted seeds. During the second test, i.e., seeds (untreted s well s coted) stored for 2 months, germintion ws still effectively nil from coted seeds t IOC, but norml from untreted seeds. In this test, prdoxiclly, coted seeds germinted s well s untreted seeds (except from tretment 3), but germintion from coted seeds t 21C ws noticebly out of chrcter in comprison with germintion in the previous nd ll subsequent storge-period tests. Although no stisfctory explntion hs been found for these nomlies, it is interesting to note tht only germin tion from R-55 tretment 3 ws consistently nd bnormlly poor reltive to ll others regrdless of the length of storge, nd this ccounts for the tretment 3 pttern in Figures 5 nd 6. Otherwise, length of storge hd no pprecible effect on germintion of either coted or untreted seeds t ny given temperture (Fig. 6), nor on the pttern reveled when ll storge tretments were combined (Fig. 5). Aside from somewht slower germintion during the first week fter seeding (< 1% over ll) nd perhps slightly less uniform germintion during tht initil period (Fig. 7, Tble A.7) there ws no pprecible difference in the germintion pttern of coted seeds stored for pproximtely 4 yers nd those stored for only 1% yers. After 6 yers of storge, germintion during the first week fter seeding ws 28% lower from untreted seeds nd 32% lower from coted seeds (men of ll five R-55 tretments) thn it ws fter 4 yers of storge. However, by the end of the second week it ws only 6% nd 3% lower from uncoted nd coted seeds, respectively, thn it ws fter 4 yers of storge.

15 O o CM o cm o o o o 1 n:. i Ell o DC o o u w c! T^ U O OJ (U tu 4-1 cn in co t i) w T3 U l]l nj w n o O.-I o oo H - I! m 4J - 4J dj M H 11 > ; & to tj o H nl u to ni J tf H h m ^ jj or p rt Fl p.-h rt S tf <U fl) O 51 *J vi n ) -I P4 Hi O cc tl CO O m RHINOH* SHIMOW Slll«OW9 SHI MOW 1 SM1NOHS1 5II1F1HH SHI MOW

16 CD I" > O CO " :o c o ni PERCENT GERMINATION 1

17 DISCUSSION AND CONCLUSIONS Results of the tests with Arsn-coted blck spruce seeds pper to support the premise behind the province of Ontrio's Arsnltex-luminum tretment1* of blck spruce seeds for direct seeding, nmely, tht Ar'sn hs no dverse effect on germintion of blck spruce seeds. The germintion response of better, fster germintion t 21C, 32C nd IOC (in tht order) is eqully true for Arsn-coted nd un treted seeds. The evidence indictes tht coted seeds germinte s uniformly s untreted seeds nd tht stored coted seeds germinte s well s stored untreted seeds up to nd including 18 months of storge. Arsn-coted jck pine seeds exhibit somewht different germi ntion pttern. Although germintion from Arsn-coted jck pine, like cht from Arsn-coted blck spruce, is better t 21C thn t 32C nd IOC, coted jck pine seeds never germinte s well or s uniformly s untreted seeds. Storge hd no effect on untreted or on coted seeds except, perhps, t IOC where germintion from coted seeds ws some wht poorer nd more irregulr thn from untreted seeds. The germintion responses nd ptterns of R-55 coted blck spruce re quite similr to those of Arsn-coted blck spruce, so tht, side from the pprent nomlies t IOC nd 32C with freshly coted seeds nd t IOC nd 21C with seeds stored for only 2 months, neither the R-55 coting nor the length of time coted seeds were stored (up to nd including 18 months) hd ny prcticl dverse effect on germi ntion. This conflicts rther mrkedly with Rdvnyi's (1975) finding. He reported tht germintion from R-55-coted blck spruce seeds, which equlled tht from untreted seeds to begin with (92%), dropped to 62% nd 8% fter 1 nd 2 yers storge, respectively. The generl similrities in the blck spruce germintion/temperture/storge responses between the Arsn nd R-55 cotings, whose only common ingredient is the ltex binder, suggests tht it my be this component tht is responsible for ny subtle effects the cotings do exert on germintion rther thn ny toxic effect of the Arsn or R-55. Although it is now irrelevnt becuse the product is no longer mnufctured, except for the nomlies t the -month nd 2-month storge tests (Fig. 6), there is little to choose mong the five R-55 tretments t IOC, nd even less t 21C, insofr s their effect on germintion is concerned. However, the consistently poor germintion response from tretment 3 nd the irregulr response from tretment 2 t 32C ppers to fvor the selection of tretments 1, k nd 5. ''See Appendix HI for resume" of supplementry study (unpublished) of ltex-luminum coting currently used by the province of Ontrio.

18 In conclusion, neither Arsn nor R-55 hve ny pprecible dverse effect on germintion of blck spruce seeds except t low tempertures (IOC) where R-55 depresses germintion slightly below tht obtined from untreted seeds. Coting jck pine seeds with Arsn invribly depressed germi ntion but only pprecibly so t low tempertures (IOC). Length of storge up to 18 months hd no prcticl effect on germintion of Arsn-coted blck spruce seeds, but storing Arsncoted jck pine seeds depressed germintion t low tempertures (IOC). Length of storge up to 18 months hd no prcticl effect on germintion of R-55-coted blck spruce t ny of the test temper tures. Even longer storge (pproximtely 4 yers) hd no more dverse effect on germintion of R-55-coted seeds t the optimum germintion temperture (21C) for this species thn it did on untreted seeds. LITERATURE CITED FRASER, J.W Seed tretments (including repellents), p in J.H. Cyford, Ed. Direct seeding symposium. Dep. Environ., Cn. For. Serv., Ottw, Ont. Publ p. FRASER, J.W Direct seeding blck spruce - is it fesible? p in Blck spruce symposium. Dep. Environ., Cn. For. Serv., Sult Ste. Mrie, Ont. Symp. Proc. -P p. RADVANYI, A A new coting for coniferous seeds. For. Chron. 46(5). 3 p. RADVANYI, A Germintion of blck spruce seeds: how storge ffects seeds treted with R-55. J. For. 73(3):165.

19 APPENDICES

20 APPENDIX I R-55 Seed-coting Tretments (Blck Spruce) Seeds coted with R-55 were treted by the Cndin Wildlife Service, Western Region, s follows (A. Rdvnyi, Cndin Wildlife Service, Edmonton, Albert, personl communiction): cotings contined () 4:1 R-55:grphite mixture, (b) Dow ltex 612, diluted 1:9 ltex: wter cidified with HC1 to bring the ph from 8.2 to 4.8. Coting cu. cm ltex solution pplied in one lot - gllon-size mixer rotted 2-3 min before R-55/ grphite pplied - 75 g R-55/grphite powder pplied in three smll portions - seeds tumbled pproximtely 3 min more, then emptied nd shken in fine mesh sieve to remove surplus powder - coting ws irregulr under microscope. Coting 2. - sme s 1 except for 4 min tumbling fter seeds wetted with ltex nd before powder dded - coting ws still somewht irregulr. Coting 3, - ltex incresed to 3 cu. cm - 75 g R-55/grphite powder - coting ws still ptchy. Coting 4. - ltex decresed to 2 cu. cm - 75 g R-55/grphite powder - coting improved but some lumping of powder still occurred. Coting cu. cm ltex - 75 g R-55/grphite powder - 4 min between ltex nd powder ppliction; ltex dded using pipette, giving very fine strem pplied while mixer in motion - coting more uniform. Arsn Seed-coting Tretments (Blck Spruce, Jck Pine) Seeds coted with Arsn were treted by the Ontrio Ministry of Nturl Resources, Tree Seed Plnt (C.H. Lne, Ontrio Ministry of Nturl Resources, Toronto, Ontrio, personl conmuniction) using the following formultion for 1-lb (4.5 kg) seed lots: Arsn 42S Dow ltex 512R Distilled wter Aluminum flkes 6.6 fl oz (187.4 ml) 1. fl oz (28.4 ml) 9. fl oz (255.6 ml) 1. os (28.3 g)

21 APPENDIX II Tble Al. Men cumultive percent: germintion of blck spruce seeds Cll storge periods combined) 7, 14, 21 nd 28 dys fter seeding t IOC, 21C nd 32C.

22 APPENDIX II (continued) Tble A2. Men cumultive percent germintion of blck spruce seeds by seed tretment nd temperture 7, 16, 21 nd 28 dys fter seeding for ech storge period. Months of storge Dys since seeding Blck Spruce - Percent Gemintion" Control Arsn IOC 21C 32C IOC 21C 32C There is no sxgniricnt difference (p =.5) between vlues joined by the sme verticl line or between those within the sme tretment with the sme lower cse letter(s) in the sme horizontl line

23 APPENDIX II (continued) Tble A3. Men cumultive percent germintion of jck pine seeds Cll storge periods combined) 7, 14, 21 nd 28 dys fter seeding t IOC, 21C nd 32C.

24 APPENDIX II (continued) Tble A4. Men cumultive percent germintion of jck pine seeds by seed tretment nd temperture 7, 14, 21 nd 28 dys fter seeding for ech storge period. There is no significnt difference (p =.5) between vlues joined by the sme verticl line or between those with the sme lower cse ietter(s) in the sme horizontl line.

25 Tble A5. Men cumultive percent germintion of blck spruce seeds (ll storge ueriods combined) t IOC, 21C nd 32C t weekly intervls. C = Control (untreted seeds). 1-5 = Five tretments.

26 Tble A6. Men cumultive purcent germintion of blck spruce seeds by seed tretment 7, 14, 21 nnd 28 dys fter seeding for ech sunriiftft period. t i x n o rt 'There Is no significnt difference (p ^.5) between vlues joined by cht; gniti verticl line, or between those with the sme lower cse letcer() in the sme horizontl line. (eonlluucd)

27 Tble A6. Men cumultive percent germintion of blck spruce seeds by seed tretment 7 14, 21 nd 28 dys fter seeding for ech Storge period (continued). - m o» x O O P It H- s p. "There is no difference (p =.5) between vlues joined by the sme verticl line, or between those with the sme lower cne letter(s) lt\ the sme horizontl line. (continued)

28 Tble A6. Men cumullivu percent ycrniin t Ion of: blck spruce sec d by seed tru tjnent 7, 14, 21 nd 28 dys fter seeding for ditch storge period (continued). Months Ve rciiiit germint itni - lilck Sn nice of Temp. No. of CO1 K R-55-4 k (J 1 L [) 9 12 VI n no b 32 b BO n h 75.i yo 92 93'n 88 8(J s ;i yo 93 SU 89 9L u m 5H X 7 ti\ 81 8G 7 UJ 82 7 o o 32 t) lli l/i tt b 75 b b ] 2L n n 9 91 n B B 2 b 86 I) b HO U El H6 1) I'M 86 b (i 87 b is no lgni fie nt i\i f ferencu (p -.5) bee ween v Lucu joined hy th S2MHQ vert f cl or between those urlcli the sme lower cse JeLLiir(s) in Llic sme horizontl line.

29 Tble A6. Men cumultive percent germintion of blck spruce seeds by uced tretment 7, 14, 21 nd 28 dys fter seeding for ech tomic period (concluded). m "There l no significnt difference (p -.5) between vlues joined by the sme verticl line, or between those with Lhe sme Iowlt cse letter(s) in the sme horizontl line.

30 Tble A7. Men cumultive percent germintion of blck spruce seeds nd coefficients of vrition (CV) by seed tretment 7, nd 28 dys fter seeding t 21C.

31 APPENDIX III influence of Ltex 633 on Gevmini'Lon of White Spruce, Blck Spruce nd Jck Pine Seeds 3y Che time the studies presented in this report were completed, Arsn hd been dropped from the Ontrio Ministry of Nturl Resources (CvINR) Arsn + ltex + luminum seedcoting tretment, nd seeds were coted only with ltex nd luminum flkes. Presumbly, the rtionle ws tht seeds hd to be "lubricted" (luminum flkes) in order to pss through mechnicl seeders undmged, nd ltex ws used to "bind" the luminum flkes to the seedcoc. Although the premise tht such lubri ction ws essentil ws never, to my knowledge, substntited nd/or documented, seeds for direct seeding were still being coted with ltex nd luminum in Erly in 1979, becuse Dow Ltex 612R ws no longer vilble, OMNR begn using Dow Ltex 636 s the binder in ltex + luminum seedcoting. They tested the effect of this new ltex on germintion of conifer seeds with no untowrd results (personl communiction from C.H. Lne) under their test conditions, i.e., lternting tempertures, both of which re within the optimum germintion/temperture rnge for the species tested. In ddition, with untreted seeds s controls, the effect of the new tretment on germintion of blck spruce, white spruce (Pioe glu [Moench] Voss) nd jck pine seeds ws tested t the Gret Lkes Forest Reserch Centre. Aprt from the effects of storge, these tests prl leled those for testing the previous Arsn coting nd the second series of R55 cotings. Men cumultive percent germintion of blck spruce seeds by temperture nd seed tretment t weekly intervls fter seeding. There is no significnt difference between percentges joined by the sme verticl line, nor between those with the sme lower cse letter in ny horizontl line.

32 APPENDIX III Continued) Results t the optimum temperture (21C) indicte tht, other thn delying germintion slightly during the first week fter seeding, the new ltex tretment hd no dverse effect on germintion of blck, spruce seeds. Even t Che upper end of the rnge of optimum germintion tempertures for this species (32C), where germintion ws somewht slower thn t 21C, the ltex tretment did not ffect germintion dversely. At the opposite end of the optimum temperture rnge (IOC), germintion from ltex-coted seeds, three weeks fter seeding, ws significntly lower thn from untreted seeds, but ws no longer so by the end of the fourth week. Germintion from coted jck pine seeds ws significntly lower thn from untreted seeds t ll three tempertures t ll times up to nd including 28 dys fter seeding. This indictes tht the new coting does inhibit germintion of jck pine seeds. It is debtble whether the sttisticl differences t 21C beyond the 14th dy hve nyprcticl significnce, but those t IOC nd 32C certinly do. Hen cumultive percent gstnintion of jck?ine seeds by cesperture nd seed tretment : «ekly Intervls fter seeding. See footnote to blck spruce tbultion for indictions of scfsc'cl sigtiiticnce. : ss ssir- ijo. dys of Control '-"nlte Spruce - Percn- Gei 32C

33 APPENDIX III (concluded) The new coting hd no significnt effect on germintion of white spruce seeds t the optimum germintion temperture (21C) nor t 32C where it ws < 1% even from untreted seeds, but it did inhibit germintion significntly t IOC. If one considers only the results t 21C there is no evidence here tht the new ltex luminum coting hs ny dverse effect on germintion of blck spruce, white spruce, or jck pine seeds. However, such idel temperture conditions never occur in the field. Therefore, the results t IOC nd/or 32C re interpreted s indicting tht the coting probbly will hve some dverse effect on germintion under field conditions, prticulrly on germintion of white spruce nd jck pine seeds. Hence, some considertion might be given to whether lubricting the seeds by coting them with ltex luminum to fcilitte seeding them mechniclly which is presumbly the only reson for the coting is worthwhile trde-off ginst potentilly dverse effect on germintion, depending upon the seedbed temperture conditions during nd following the seeding.