Forest Development Research PROGRAM Manning Diversified Forest Products Research Trust Fund MDFP 6 /96 Basal Bark Application of Release (TM) Herbicide For Mbcedwood Management 1996 Interim Report ENVIRONMENTAL PROTECTION ^'V'} ; >■; ;■ • ‘1 n : '.'' '■' '■ .c’-i v. ;^- ■ -'v'y - :'^''*i' Manning Diversified Forest Products Research Trust Fund MDFP 6 /96 Basal Bark Application of Release (TM) Herbicide For Mbcedwood Management 1996 Interim Report April 1997 By Steve Blanton MDFP Ltd. Manning, Alberta Canada Pub. No. T/382 ISBN: 0-7732-9988-2 - Disclaimer - The study on which this report is based was funded by the Manning Diversified Forest Products Research Trust Fund (MDFP) which is a component of Alberta’s Environmental Protection and Enhancement Fund (EPEF). The views, statements and conclusions expressed, and the recommendations made in this report are entirely those of the author(s) and should not be construed as the statements conclusions, or opinions of members of the Manning Diversified Forest Products Research Trust Fund or of the Government of Alberta and its EPE Fund. Basal bark application of Release® Silvicultural Herbicide for mixedwood management 1996 - Interim Report Sponsored by: MDFP Research Trust Fund Manning Diversified Forest Products Ace Vegetation Control Service Ltd. DowElanco Canada Inc. Manning Diversified Forest Products - Mixedwood stand tending, 1996 Interim Report Introduction A significant portion of Manning Diversified Forest Products Ltd. quota area occurs in the B. 18a (Boreal Mixedwood) forest region (Rowe, 1972). This forest type is characterized by mixed stands of aspen (Populus tremuloides), birch {Betula papyrifera), balsam poplar {Populus balsamifera), white spruce (Picea glauca) and balsam fir {Abies balsamea). The region is occupied by associations of tree species rather than dominant stands of single species, hence the name mixedwood. “Natural” regeneration of upland stands following fire results in site dominance by aggressive pioneer tree species (aspen and pine), followed (over an extended time span) by white spruce and even later by balsam fir ingress. At maturity this process results in a complex mosaic of species and individual trees both within stands and across the broader landscape. While harvesting this forest mimics natural disturbance and renewal to some extent, it does not duplicate the natural process of renewal (Johnston, 1995). Aspen is an aggressive invader of recently cutover sites due to its ability to reproduce fi^om root suckers, which are not destroyed by logging as they are by wildfire. Forest managers rely on site preparation and planting conifer seedlings to hasten white spruce establishment, and hence, the entire renewal process. Tending treatments to limit aspen growth and density are fi-equently prescribed following white spruce establishment. Tending does not eradicate aspen from the developing stand; it sets out to better mimic the balance between aspen and white spruce which occurs in “natural” regeneration processes following fire. Traditional tending methods in Alberta have been motor manual release treatments using brushsaws in younger stands and chain saws in older stands. Tending treatments remove competitive trees and shrubs fi-om the vicinity of established conifer seedlings (or saplings). Motor manual treatments are of limited effectiveness in controlling aspen due to its ability to resprout following cutting. Further, motor manual treatments become difficult and expensive once target species are more than 5 cm in diameter. Alternate tending strategies must be developed for tending older (20 years +) stands. Prepared by; Incremental Forest Technologies Ltd. Manning Diversified Forest Products - Mixedwood stand tending, 1996 Interim Report Manning Diversified Forest Products Ltd. timber quota area contains approximately 8000 ha of reforested cutblocks which might benefit from tending. Much of this area is sufficiently old to drastically limit use of motor manual tending. Manning Diversified Forest Products Ltd. assessed tending alternatives based on the following criteria; 1 . Effectiveness 2. One pass management of all crop species (conifer and deciduous) 3. Safety 4. Cost 5. Impact on other resources/land uses This assessment suggested that basal bark application of triclopyr ester herbicide (Release® Silvicultural Herbicide - 480 g/L triclopyr ester) might be a viable tending option. The method is target specific and easily used on trees and shrubs up to 1 5 cm in basal diameter. An experiment to verify the effectiveness of the herbicide treatment in stand tending - including both brushing (control of selected aspen) and spacing (adjusting white spruce densities) was designed. Rather than focus on tree responses the experiment considered the effect of basal bark treatment with Release® on both tree species and a range of other site values. This paper reports establishment of, and first year data fi-om, that experiment. Project Objectives 1. Assess the effectiveness and cost of low volume basal bark application of Release Silvicultural herbicide diluted in mineral oil for managing - brushing and spacing - all crop tree species on post juvenile mixedwood sites. 2. Compare the effectiveness and cost of chainsaws and brushsaws for spacing and tending on similar sites. Prepared by: Incremental Forest Technologies Ltd. Manning Diversified Forest Products - Mixedwood stand tending, 1996 Interim Report 3. Qualitatively compare the foDowing factors between motor manual and herbicide tending: a) short term slash loading and fire hazard arising therefrom b) longer term impacts on forest health - particularly extent of fi-ost damage, windthrow, weevil attack, physical damage. c) off target impact of Release on crop trees adjacent to treated trees (of the same species.) d) soil retention of Release herbicide. e) bird use of treated and untreated areas at 5 intervals annually (spring migration, nesting, fledgling, fall migration and winter.) The overall objective was to compare motor manual and Release herbicide tending as mixedwood management tools. Work performed in 1996 Two regenerated cutover areas were identified in the South Hotchkiss oilfield. These areas were cut in 1971 (25 year old stand) and 1981/82 (15 year old stand). Both areas are readily accessible on high grade road and quite uniform in aspen and white spruce size, age and density. Manual tending was prescribed using chain saws on the older stand, brushsaws on the younger stand. Both stands were also treated with Release® diluted in isoparaflfinic mineral oil. Several areas were sampled and laid out in the two stands. Initial treatment areas were used to teach crews stand reconstruction, that is; crop tree selection based on: 1 . variable density spacing rules 2. crop tree health, thrift and vigor 3 . species priority ranking Prqjared by; Incremental Forest Technologies Ltd. Manning Diversified Forest Products - Mixedwood stand tending, 1 996 Interim Report Once the crew became skilled in crop tree selection and use of specific treatment techniques they were moved into measured areas where productivity could be monitored The productivity assessment areas were marked with permanent sample plots to monitor; 1 . crop tree response to treatment, 2. slash (and hence fuel) loading, 3 . soil dissipation of the herbicide, 4. non-target effects of the herbicide established. Pretreatment measurements of basal area growth of trees, density, bird use, and tree species composition were made in the sample areas. Following treatment density of aspen and white spruce saplings was re-measured in motor manual treatment areas (assessments in Release plots could not be made due to slow kill of white spruce saplings with this treatment.) Slash loading after treatment was assessed in all treatment areas. Bird surveys were conducted at the intervals specified. Prepared by; Incremental Forest Technologies Ltd. Manning Diversified Forest Products - Mixedwood stand tending, 1996 Interim Report Results of 1996 work Productivity and Cost Study Productivity of stand tending methods are shown in Table 1 and Figure 1 . Chain saw tending of the 25 year old stand was slowest with 84 person-hours required to treat one hectare (or a rate of 0.012 ha per hour), this was followed by brushsaw tending of the 15 year old stand with a productivity of 21 person-hours per hectare (0.05 ha/hr). Basal bark treatment of the older stand required 8.2 person-hours per hectare (0. 12 ha/hr), whilst the younger stand required only 7.2 person-hours per hectare (0. 14 ha/hr). Both motor manual tending treatments were more costly than herbicide tending, even including the cost of herbicide and oil. Figure 2 and Table 1 show cost comparisons between the various methods. $15 12 per hectare for chainsaw tending (25 year old stand) and $348 per hectare for brushsaw (15 year old stand). Basal bark tending of the older stand cost $254 per hectare due to slightly lower productivity and slightly higher herbicide use rate than treatment of the 1 5 year old stand ($208 per hectare.) From a cost standpoint it appears better to tend early and if that is not possible to use basal bark herbicide not motor manual tending. Initial Densities and Growth Rates Average pretreatment densities of both aspen and white spruce are shown in Table 2 and Figures 3 and 4. Taken alone the density data are somewhat misleading -white spruce appear to dominate the older stand at 16,600 stems per hectare. These densities were due to the original reforestation treatment being blade scarification and seeding (followed by some good natural seed crops. This resulted in dense clumps of white spruce seedlings suppressed by competition among themselves and from the adjacent large aspen. Growth was measured as periodic basal area increment - measurement of increases in area of the Prepared by; Incremental Forest Technologies Ltd. Manning Diversified Forest Products - Mixedwood stand tending, 1996 Interim Report brushsaw treatment increased use. These data must be regarded as preliminary until more bird use surveys have been conducted over the next two years. Herbicide Residues Soil samples to assess herbicide residues were taken in front of six crop trees and behind sbc crop trees (relative to the direction of herbicide application); these samples were composited into a single analytic sample. This procedure was repeated twice at each sample timing, in June and October. Samples were analyzed for triclopyr acid with a detection limit of 0.5 PPM. Table 10 reports results of these samplings. Triclopyr residues were found in both behind tree samples in June and in one behind tree sample in October. The levels of triclopyr found are near the detection limit of the method used so should be considered to indicate presence rather than be used for quantitative comparison. Discussion and Conclusions Basal bark tending is clearly more productive and less costly than motor manual tending. Differences in productivity (and cost) are magnified as stand age increases. Fuel loading and fire hazard were much greater following motor manual tending. This is due to a greater accumulation of fuel and especially an increase in lighter fuels which contribute significantly to rapid fire spread. Herbicide residues in soil (near the limit of detection) were present on the site 4 to 5 months after treatment. Prqjared by; Incremental Forest Technologies Ltd. Manning Diversified Forest Products - Mixedwood stand tending, 1996 Interim Report Given the preliminary nature of many results few inferences can be made as to the effect of tending method on forest health; crop tree growth; vigor and thrift; or other longer term impacts on the site. FoUow up monitoring of forest health, response and soil residues must occur in 1997 and 1998 to address these questions. Prqjared by: Incremental Forest Technologies Ltd. MDFP Mlxedwood stand tending 1996 Report — h M C/5 r* CD CD Ot < CD >< CD 3 Q. CD CD CD (A ;;; to CD CD CD CD CD n CD CD 3- CA c (A CD CD CA CD O- 5' CT CD CA CD CT CD CA CD $ $ 5' ?r O' CD O’ CD CD 3 CD 3 -r O' CO. CT g. o' o' o* 3' CO CO CO.' CL CD CD CD CD O O Q. o' o' CO (O 00 ■O CD -1 T3 CO -T O O Z2 Q. O ^ 5 <: O) D) NJ -D Q) CO -D bol: O EU CD I (D O' C O' E Si, ® c (A n •CA- ro -CA- CJ •CA _» ro ' 0 0 vj CD CD •CA 00 00 CT cn b b ■Si. 4c 0 0 °s Table 1. Productivity, herbicide use, and cost of mixedwood stand tending treatments. years years g"o ® a 30 3 0000 00 OOOOP-J^-Ji- to ^ 0> 00 iO ^ V V \ V V VA a > (Q o 1-4 a ft) CD r-t^ ^3- o Cl- C/5 Figure 1 . Productivity of stand tending 25 years 15 years Q. > in o lo ^ o> 00 o o o o o o o o o o o o NO 4:^ o o o o a> o o Figure 2. Cost of stand tending treatment methods. MDFP Mixedwood stand tending 1996 Report CJ1 < (D Q) CA ro cn < a> Q) (A » 3 Q. CD CO CD ^ > S CA d. -o ® 3 C/5 "D C o CD S CA d. TD CD 3 ■o c o CD CO T3 CD O CJ N5 o CO M ^ cn cn O Oi ^ ^ Q. ® S* 3 I CD 'O o ^ o O 6 o o_ o CA

o 3 o o -o o ^ o 00 00 (35 CO CO O O C35 -» 00 ro ^ CD CO O Table 2. Average pretreatment tree densities, ail treatment types. cm cm cm cm Stem diameter class o o oo(/> ip Figure 3. Average pre-treatment densities, 25 year old stand. 0-<3 3-6 6-9 9-12 12-15 cm cm cm cm cm Stem diameter class gure 4. Average pre-treatment densities, 15 year old stand. Manning Diversified Forest Products - Mixedwood stand tending, 1 996 Interim Report base of individual trees in specified (2 year) time intervals. From the growth data (Table 3 and 4, Figures 5 and 6) it is apparent that in both stands white spruce is merely present not growing vigorously. This is very common in regenerated mixedwood cutovers. No growth responses to treatment can be assessed at present, in fact, growth responses are not likely to become apparent until 3 years after treatment. Aspen densities were higher in the 25 year old stand than in the 15 year old stand. White spruce densities were much higher in the 25 year old stand than in the 15 year old stand. In both cases differences are likely due to differences in establishment practice. The blading treatment used to prepare the older site for seeding likely stimulated aspen suckering causing high initial aspen densities. Direct application of seed, followed by good seed years resulted in an overabundance of white spruce seedlings in the older stand The younger stand was site prepared using a spot scarifier (Bracke) which did not stimulate aspen suckering as dramatically. Also, white spruce seedlings were planted on the site giving better density control. The spot scarifier was less likely to result in reproduction fi-om natural seedfall further contributing to more evenly spaced and less dense white spruce seedlings. Changes in Density Following Treatment Due to the subtlety of Release® symptoms on white spruce saplings changes in density following treatment can only be reported for motor manual treatment. (Changes in density in Release® treated plots will be reported in the 1997 report.) These data are shown in Table 5 and Figures 7 and 8. Aspen in the older stand had begun to express dominance among themselyes, thus larger aspen were thriftier, healthier trees and were selected as crop trees; with smaller, less vigorous trees being removed to reduce competition to aspen or white spruce “crop trees”. In the younger stand dominance was less clearly expressed so tending removed a more uniform distribution of aspen sapling sizes. Prepared by; Incremental Forest Technologies Ltd. Table 3. Periodic basal area increment, y species, 25 year old stand. Basal area increment (mm2) Stand age (vears) White spruce Aspen 0-2 12 105 2-4 12 125 4-6 12 127 6-8 16 119 8-10 22 122 10-12 Not available 141 12-14 42 114 14-16 126 16-18 110 18-20 Insufficient data 20-22 Insufficient data MDFP Mixedwood stand tending 1 996 Report 5‘OJ 3 £i 0) g o SSL wOaOIOiDkG> OOOOOOOOO Figure 5. Periodic basal area increment, 25 year old stand Table 4. Periodic basal area increment, y species, 15 year old stand. Basal area increment (mm2) Stand age (years) White spruce Aspen 0-2 4 59 2-4 4 105 4-6 3 118 6-8 4 107 8-10 5 118 1 0-1 2 Insufficient data 1 1 3 12-14 116 MDFP Mixedwood stand tending 1 996 Report Figure 6. Periodic basal area increment, 15 year old stand. MDFP Mixedwood stand tending 1996 Report a 3 » a. w a 3 S O CD II o 3- -D -n QJ o ^ 3 Crt CO CQ '7 • CD rt. ^ =;■ 5 J Q. g CD 3 D CD Cfl D o 3- -D 0) o ZJ Crt (Q >-*■ CD A = • CD J 03 cz. g CO 3 3 CO cn 3 ro N3 .P' C33 o <33 <33 ~ <33 O o O 0^0 O o O O O ro ro O o o O O o O o o O o 3 N3 o o o O O O O O O N> -* C*J O O O O O O O w CD 3 (0 s' fl» O) F « c^ if <33 00 O O o o o o o o cp i:. ro CD 3 N3 N3 O O O O O 00 00 o o o o o cn CJV'O O ^ O O O o o o cn cji O O <33 C33 O O O O O O Table 5. Changes in aspen density following motor manual stand tending treatments. cm Stem diameter class lO lO CO w cji o cn o CJ1 o cji o o o o o o o oooooooo Figure 7. Changes in density following chainsaw treatment, 25 year old stand. cm cm cm cm 15 cm Stem diameter class _ a S3 sr M = N> M O Ol O cn O Ol O O O O O O O O O O O O O O Cd 4:n. ^ 07 Ol O Ol O O O O O O O O O O 6 Cd o> NJ ^ CJ ^ 00 CO 5 00 -4 o o o ^ Oi o o> 3 0 V* 5- CJl o 3 -4i o c 3 a. •o 0 ^ S 0 O 0 3 2 o -* o ^ Table 6. Slash loading following stand tending treatments. Fuel diameter class w ^3- c II S § ^5''S o « o to ^ a> 00 o ro ^ o o o o o o o CD K in <-*■ P P O- Figure 10. Post treatment slash loading, MDFP Mixedwood stand tending 1996 Report S 2 0 S’ £> 2 3 -a ^ a — ® n 3 a O D X o 3 o a ^ 5 n X ® « Q. ? II 5 CD S 33 Crt ^ i-l • T-l _ =5 S . ? S o' 5 O 0) S O’ Z < O CD X ST o S S ■< 5^ S = o § S X Cfl X X O • C to O’ o :? < 5’ o o = to- < 00000-‘-»-‘-‘00000-*-*-*0000000000000Ni-*ArsjJk ooooowXNj?:ooooo-‘-t‘-'00oooooooooooN3(jia5i» ->-*00-‘0000-‘0-*0-'000-‘ONJ-*-‘S->-*N)-*OONJfo -‘(000N>0000-»0-*0-‘000-‘0N>-*-*^-‘N>-»00t0NJC«>-‘Au 000000-*0-*00000-*0-‘-*ONJ-‘ O -tk 05 W Ca> OI ISJ a o ^ = ro § oooN>oooooo-*o o o o o o o N5 fo -• -» O ooooooooooooooooo-‘-*oooo-‘jkwoooo-*oic*5 § a • 0 O’ ooooooooooooooooo-»-*oooo W o o o o - P? lo r* T* -*-‘-*-*-*-*roNjN>r«oMNJc-5wwc;io5a5COcc cn 05 CO CD -• Table 7. Total observations and ranking, May thru October, 1996. MDFP Mixedwood stand tending -‘NJ-*N3N3N)^N)Q-*-‘-*-‘-‘-‘-e‘-‘N)rsJN}N3N34:iOJ4^CAJ^CDCO^^|^[j^ 0000000000-^0000000000-‘0-‘0-‘N3 0000000000-‘0000000000-‘0-*C-‘CD NO N3 OD CJ1 o o O- ce 0 < o 3 Co CO NO g 01 >vj _^00-‘-‘^00000-‘ -»OON0N0N0OOOOO-* -‘OOOO-‘OOON0OO JS-OOOO-'OOONOOO NO ‘ A NO NO NO NO cn ^ NO NO Table 8a. Bird observations in overall research area. MDFP Mixedwood stand tending 1996 Report 9 S CO CO 3 -D 2. ® 0)' i| CO CO o 3 o; O 3 < BJ ^ a o- » c CO H o 5- S CO ® I H 3 O 31 ^ ^ k ^ a 5- ® $ ffi 3- 0) Q. cu O' ^ 3) CO -o X $ 5’ n CD X" CO H $ ® 3 = 3 CD < o ® o OT < •D < ® 3 -* C « < ■a < Q} o cn I o -► E" :r 3' 3 3 CI) c ® 7 ® < oooooooooooooooooooooooooooo CO O OOOOOOOOOOOOCOOOOOOOOOOOOOOO-^-»O^COO 00000000000000000000004:^00-* o ro o o 3 • I. 00000000000000000000004:*00 O N) O O OOOOOOOOOOOOOOOOOOOOO o o OOOOOOOOOOOOOOOOOOOOO 00M0-t^00-*-*00 Table 8b. Bird observations in younger stand MDFP Mixedwood stand tending 1996 Report ^ 9 5" (O u n ■D ^ ® a> (O 2 I i CO n 3 U O 3 < 0) < Q. a- oj C cQ ^ o 5- g C£3 ® ? S $ SJ I' ^ CD ffi 3T Q. 03 cr ^ 03 ^ 3J cn S ® ^ a ^ to c a 5 =; o ^ -r ® ^ to CD o' ^ O 7T ?r c cn -I f 5 < o ^ cr ^ 5' o Cn 33 33 Q c a -I O CD ® ^ o ^ ^ 'a' a m < Q- o |- S o o o c ooooooooooooo ooooooo-^-*-^ fvj _» _» CO ooooooooooooooooo ooooooo-*-^-^-* ooooooooooooooooooo o o o o o O O O N3 ooooooooooooooooooo o o o o o O O O CO s OOOOOOOOOOOOOOOOOO-^OOOONJO-* o o o OOOOOOOOOOOOOOOOOO-^OOOOMO-^^OOO O NO -» ro s Table 8c. Bird observations in older stand. Young Older Stand Stand a. w ~o CD g CD CO 2: c 3 a* (D Figure 1 1 . Number of bird species observed, by treatment. MDFP Mixedwood stand tending 1996 Report S 2 ? 01 0) A c e w n I -t 3 = o 3 S I ? > n 3 (S 3 O ■O 2. 5’ ® 3 5! t r < S O 5. O Q. ? 03 ^ o • ; Incremental Forest Technologies Ltd. ^ /( 1 iMduuiidi uuidiy ui udiidud Bibliothgque nationale du Canada 3 3286 51357 0438