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GERMINATION AND FIELD ESTABLISHMENT OF JUNIPER IN THE SOUTHWEST James T. Fisher, Gregory A. Fancher and Robert W. Neumann

ABSTRACT: Studies were conducted to determine introduced species (Balzar 1975). Establishing reliable methods for germinating and native P-J woodlands speeds the progression from establishing Juniperus monosperma. Poor early seral stage vegetation (annuals and germination is caused by a germination inhibitor herbaceous perennials) to longer lived woody in the seed coat and phYSiological dormancy. species (Wagner and others 1978). Also. it is Germination rate and value were significantly becoming increasingly apparent that P-J improved when seeds were leached 48 hours with woodlands should be conserved for their H0. or treated with ethephon or H 02 plus GA3 2 0 2 renewable products and uses (Jensen 1972; Lanner before stratification at 4 C. 1977; Short and McCulloch 1977). Establishment studies at three Nev Mexico sites evaluated the effects of planting date. mulch, Revegetation programs in the Southwest have drip irrigation, fertilizer and rodent rarely included one-seed juniper (Juniperus protection on juniper seedling survival. Two monosperma) because of unreliable seed years after planting, survival rates for the germination in nurseries and a lack of . best treatment combinations ranged from 70 to information on establishment techniques• 99% among sites. July was the superior planting Efforts were begun in 1979 in cooperation with date for the site near Raton, New Mexico. the U.S. Forest Service to identify reliable Drip irrigation proved superior to mulch. pregermination treatments and subsequently in Plastic mesh was essential and was more 1981 to develop revegetation practices. Because effective than animal repellant for rodent greenhouse culture of containerized one-seed protection. juniper varies little from that routinely used to grow other junipers, seedling production vas omitted as a research objective. The studies INTRODUCTION conducted will be highlighted follOwing brief reviews of information available from other Pinyon-juniper (P-J) woodlands occur extensively sources. in the West and are frequently razed by mining operations. particularly coal stripping. In Nev I Mexico, topography of surface-mined land ranges JUNIPER SEED GERMINATION i ! from flat to rolling hills. Hany areas include badlands formed by steep-walled gullies Seed Production and Germination Properties ·1 separated by rugged rock ridges. Revegetation can reduce erosion and restore aesthetic values. One-seed juniper trees produce seed when 10 to I but restoration is difficult because of low 20 years old. Flowering occurs from January to rainfall, wide temperature extremes, animal June and the fruit is formed by the fusion of a depredation and rugged topography (Schubert fleshy female flower into an indehiscent 1977). Because native plants are well adapted strobilus commonly called a berry (Johnsen and to regional conditions. native plant species Alexander 1974). Large seed crops are produced often can be established more easily than every 2 to 5 years and ripen in August or September of their first year within blue or purple berries.

Paper presented at the Pinyon-Juniper The seed coat consists of an outer fleshy layer Conference, Reno, Nevada, January 13-16, 1986. of pectiC substances, a thick lignified stoney layer and a thin inner membranous and suberized Ne~ Mexico Agricultural Experiment Station layer. In several juniper species the hard coat SC1entific Paper No. 253. interferes with moisture uptake (Johnsen and Alexander 1974). The fleshy white endosperm of these seeds is made up of thick cells with large ~~~ T. Fisher is Associate Professor of amounts of cellulose and is surrounded by an H1lv~Culture and Tree Physiology, Department of cort1culture, New Mexico State University, Las outer layer of suberized cells (Pack 1921). Nruces, NH; Gregory A. Fancher and Robert W. Embedded within this is a straight embryo with two to six cotyledons (Johnsen and Alexander Reumann are, respectively, Associate Hanager and esearch Forester, Mora Research Center, Mora, MH. 1974). "

Germination is delayed in most junipers by Table 1.--Pregermination experiments conducted embryo dormancy and occasionally by impermeable at New Mexico State University seed coats, immature embryos or the presence of (O'Brien 1980) inhibitors (Barton 1951; Djavanshir and Fechner 1976; Pack 1921). MOisture uptake through the hilum of 1. scopulorum and 1. virginiana seed is 1. Leaching (48 hrs) apparently obstructed by a covering of vascular A. wi or wlo leaching • no strat. tissues from the fruit base. One-seed juniper B. Leach before 0, 3D, 60, 90 dy strat. seeds are reported to have dormant embryos and impermeable seed coats (Johnsen and Alexander 2. GA3 (48 hr soak) 1974). A. 0, 100, 150, 200, 250, 300, 350, 400 ppm before 90 dy strat. Johnsen (1962) reported that 1. monosperma B. 125, 250, 500, 1000 ppm ~ 90 dy germination improved following a 48-hour soak in strat. several changes of distilled water. He attributed this to the leaching of seed 3. Ethepon (Ethrel) germination inhibitors. High temperature A. 48 hra 0, 200, 400, 800, 1600 ppm after stratification (cyclic 20-300 C) or H 0 was 2 2 90 dy atrat. used to improve permeability while ch~lIing was B. 48 hrs 300, 600, 1200, 2400 ppm or required to break embryo dormancy (Barton 1951; 24 hrs ethephon (same rates) + 24 hrs Djavanshir and Fechner 1976; Van Haverbeke and 250 ppm GA3 before 0, 30 or 90 dy strat. Read 1976). High temperature or H2S04 without 4. Trts applied before 0, 30, 60, 90 dy strat. chilling, H202, removal of seed coats, dilute acids and increased oxygen pressure, light and A. GA3 (48. hr soak in 250 ppm ) carbon dioxide were ineffective in promoting B. Kinetin (" " " "25") germination of unstratified seeds (Pack 1921). C. "0 (" " " "5 % soln • ) D. 2t fir kinetin (25 ppm) + 24 hr GA3 (250 The most common treatment for breaking seed ppm) dormancy, particularly physiological dormancy, E. 24 hr kinetin (25 ppm) + 24 hr "202 (5%) is stratification of fully imbibed seeds at low F. 24 hr "202 (5%) + 24 hr GA3 (250 ppm) temperatures (0.50 _5 0 C) for up to six months. G. 24 hr "202 This generally improves germination percent and rate, and widens the temperature range over which germination will occur. For one-seed Preliminary tests determined: the time required juniper, stratification at 50 C for 30 to 120 to complete water imbibition at 240 C; the days has been recommended (Johnsen 1962), but effect of imbibition temperature (40 C vs. 240 may be unnecessary for some seedlots (Johnsen C) before a 90-day stratification on 1962; Riffle and Springfield 1968). However, germination; and effects of germination chamber cold stratification reduces the nurseryman's photoperiod (8 hr light vs. no light) and flexibility and exposes seed to microfloral temperature (20-300 C vs. 20-350 C). Studies degradation. showed that seed were fully imbibed after 16 hrs, that germination percent, rate and value were significantly higher after warm imbibition 0 NMSU Cooperative Studies on Seed Treatments (24 C), and that seed germinated best when 0 subjected to an 8-hr photoperiod, 16 hrs at 20 Tests were conducted with seeds harvested in C and 8 hrs at 300 C. Results of these studies north central New Mexico in October 1979 to were applied to pregermination tests. evaluate the effects of several pregermination treatments on 1. monosperma seed germination Chemical induction tests involved placing seeds (table 1) •. Cones were depulped by a procedure in 20-ml solutions containing the respective described by Van Haverbeke and Barnhart (197R). chemical. Seeds were maint~ined at 24 0 C for Debris and void seed were removed by flotation the times indicated in table 1. and a South Dakota seed blower. Seeds were X-rayed and subjected to a tetrazolium salt test at the National Tree Seed Laboratory to Leaching significantly improved germination determine percent viable seed per lot. percent, rate and value. Leached seeds germinated rapidly to a high percent while Tests evaluated germination percent after a control seeds germinated more slowly (fig. 1). I 40-day period, germination rate and germination In addition, there was 8 positive linear value. The highest daily rate (peak value). was response as stratification after leaching used as an index of germination rate. . increased from 0 to 90 days (fig. 2). Applied Germination percent and the sum of the daily before (lr after a 90-day stratification, GA3 germination rates were used to compute had no d~tectable influence on germination. germination value as described by Djavanshir and However, "202 plus GA3 (250 ppm) resulted in Pourbeik (1976). almost total germination of viable seeds. Germinatiori percent, rate and value increased in a linear manner as ethephon concentration

294 ". GERMINATION GERMINATION VALUE 100 • 48 HR. LEACH • 0 HR. LEACH 8.0 80

60

40

20

: 2 4 6 8 10 12 14 16 5 10 15 20 25 30 35 40 ETHEPHON (PPM) (102 ) 1 DAYS I Figure l--Cumulative germination rates of Figure 3--Ethephon effects on germination value non-stratified J. monosperma seed leached for 0 of J. monosperma seed stratified 90 days before and 48 hours. treatment.

increased (fig. 3). The combination of ethephon combining 24 hr exposures to ethephon and GA3 and GA3 was ineffective. The germination apparently did not allow sufficient time for percent of chemically treated seeds was not ethephon uptake. Among ethephon-only improved by cold stratification. However, value 'treatments, high concentrations apparently gave was highest when the H202 plus GA3 and best' results because of greater absorption. ethephon-only treatments were applied in conjunction with 30 days of cold stratification, Recommendations drawn from these studies are as shown for the former in figure 4. Kinetin that seed should be leached with water at 20-24° plus H202 improv~d percent germination only and, C and cold stratified for 90 days or, for a overall, was less effective than GA3 plus H • 202 shortcut treatment, be subjected to H 02 plus GA1 or ethephon-only applied before 30 aays cold Results indicated that poor germination may stratification. The method chosen will result from the presence of a germination therefore depend upon circumstances and inhibitor in the seed coat and physiological available materials. dormancy. Gibberellic acid-only treatments probably failed because the thick seed coat disallowed uptake. Apparently H sufficiently 202 scarified seed to permit GA3 uptake, or oxidized inhibitory substances to the extent that GA3 could function effectively. The treatment I GERMINATION VALUE % GERMINATION 12.0 HZOZ tGA 0 KINETIN • H202 • KINETIN tGA " 10.0 KINETIN· 1i20 a 8.0

6.0

4.0 l

"i 1..0 I..----I_--'-_.....L._-'-_.l...-...... l.__ j o 30 60 90 30 60 90 STRATIFICATION (DAYS) STRATIFICATION (DAYS) Figure 2--Germination percent of J. monosperma Figure 4--Chemical and cold stratification 1 seed leached for 48 hours and cold stratified treatment effects on germination value of J. for 0, 3D, 60 and 90 days. monosperma seed.

295 FIELD ESTABLISHMENT OF JUNIPER Seedling containerization reduces transplant shock and permits planting when summer rains Woody Plant Revegetation in the Southwest occur in the Southwest. Preliminary studies in northern New Mexico indicate that planting In New Mexico, transplant survival is determined container seedlings in late August and September largely by moisture availability (Aldon and results in less survival and growth than in JUly Springfield 1973). Cultivation, certain types plantings (Fisher and Neumann, unpublished of mulches and drip irrigation can improve data). For some conifer species, planting in infiltration. Cultivation also incorporates late summer and fall apparently does not allow organic matter, promotes aeration and helps adequate root development before low soil roots penetrate heavy soils (USDA 1979). temperatures reduce further root extension. Mulches often improve tree and shrub survival (Springfield 1972; Carpenter and others 1978) Steps are often required to protect transplants because moisture is conserved. Mulches from animal brOWSing. Because poisons, routinely used are wood chips or straw applied repellents and trapping are either hazardous or at a rate of about 3,360 kg!ha. Straw is a unreliable, lightweight polypropylene netting or common standard against which other materials meshed tubes that physically protect each tree can be evaluated (Berg 1972). The effective have been developed and appear effective life of straw and hay mulches varies with (Campbell 1969). Tubes are marketed in a climatic conditions, but is usually about 1 variety of gauges and dimenSions, and they year. Wood residues last longer, are easier to photodegrade in the field in 3 to 5 years. apply, carry no weed seeds and resist wind movement (USDA 1979). Wood chips are often applied to steep slopes (20% or more) where NMSU Cooperative Studies on Revegetation straw mulches are less effective in preventing Practices erosion. Experiments were begun in 1981 to determine Incorporating straw into soil to a depth of 5 em reliable methods for routine revegetation of retards wind removal. Applied too heavily, a juniper on mined sites. Specific objectives thick cover of organiC mulch causes considerable were to relate establishment success to planting water loss by intercepting precipitation and date and treatments including drip irrigation, subsequent evaporation (Hodder 1974). Straw mulch, protective polypropylene mesh (SO mil) mulch greatly increases the organic matter tubes and fertilization. Research objectives content of relatively sterile spoil material. were tailored to each of three test sites in Organic matter also increases soil porosity and compliance with the most urgent needs and the aggregation (Hodder 1974). available resources. Site descriptions, methods and results are fully described elsewhere Supplemental irrigation has significantly (Fisher and others, in press). This paper will increased woody plant survival in western summarize two of the three studies. revegetation plots (Lang 1971). Drip irrigation increased survival of Juniperus scopulorum The Raton site (2,194 m elev.) is 98 km west of (Williamson and Wangerud 1980), and Atriplex Raton, New Mexico. It occurs within a major canescens (Aldon 1978). Directed watering coal field occupying dissected plateau country. reduces weed problems, soil erosion and the Mineable lenses ranging from 1 to 4 m thick are total volume of water used. Portable systems extracted by underground and surface mining. can be designed to meet the needs of remote Good stands of native vegetation occur on all sites (Garcia 1979). sites except those with shallow soil. . Douglas-fir and ponderosa pine are located on The two elements most commonly deficient on north-facing slopes; P-J woodlands reside on the disturbed land are nitrogen (N) and phosphorus more xeric sites. Mean annual rainfall is (P) (Berg 1972). Transplants often fail because 360-460 mm. Soils are derived from sandstone soil is so deficient in P that plants do not and shale and have a pH of 8.2-8.8. The extend their roots enough to exploit an adequate experimental site is level to moderately sloping moisture supply (USDA 1979). Topsoils may with 31 to 51 cm of topsoil covering spoil contain adequate N, but subsoils and geologic material. materials are usually deficient (USDA 1979). Conventional fertilizers have given erratic The Grants site (2,194 m elev.) is on La Jora results in arid regions because their salts Mesa within the Cibola National Forest. The often injure transplants. Slow release test site is surrounded by P-J woodlands and is formulations may be less injurious and provide an abandoned uranium spoil. Annual nutrients for many months. Because release rate preCipitation is 130 to 230 mm, and soil pH is is temperature dependent, more nutrients are about 8. The soil is derived from Dakota available when higher soil temperatures are also sandstone, a prominent mesa soil in the area conducive to root growth. Transplant root (Griswold 1971). growth can be greatly increased by providing slow-release fertilizer and superphosphate At the Raton site, a split-plot randomized block (Whitcomb 1977). design with six replications was used. Main plots were drip irrigation and straw mulch. Six

296 .'

subplots (three planting dates X two fertilizer Table 2.--Treatment effects on one-year survival regimes) were randomly assigned within each main of one-seed juniper seedlings planted plot. Planting dates were July and August 1981. near Grants, New Mexico and ~y 1982. Fertilizer treatments were 20 kg/m Osmoco§e (18-6-12) slow-release fertilizer plus 11 kg/m triple-superphosphate (0-46-0) ------Treatment------Survival (%) mixed with soil in the planting hole versus no supplemental fertilizer. Each subplot contained 38 seedlings spaced 0.5 m X0.9 m. The 3 Mulch Fertilizer 13-month-old seedlings were grown in 160-cm Ray Leach tubes according to procedures described by l I Wood Chips 21 g/tree TSp 98.8 A2 Tinus and McDonald (1979). 10.1g Os. 3 + TSP 97.5 A 20.2 g Os.+ TSP 93.9 AB 1 The study site was roto-tilled before planting I none 92.5 AB to improve moisture infiltration and remove No Mulch 21 g/tree TSP 83.8 B weeds. Seedlings were auger-planted. Straw 10.1g Os. + TSP 88.8 AB mulch was spread by hand and incorporated into 20.2 g Os.+ TSP 95.0 AB the top 5 to 10 cm of soil to avoid wind none 88.8 AB displacement. The drip system supplied each none/no protection4 85.0 B seedling with enough moisture to wet the soil around it to a depth of 30 cm. Drip plots were irrigated bi-monthly from May through September. Weeds were controlled by hand cultivation. 1 Triple-superphosphate (0-46-0) 2 Values with the same letter are not The Grants test evaluated Osmocote (18-6-12) and 3 significantly different at p<0.05. 0-46-0 triple-superphosphate (TSP) fertilizers Osmocote (18-6-12) along with wood chip mulch or the lack of it. 4 Treatment lacked rodent protection. Specific treatments are identified in table 2. Fertilizers were applied in shallow pockets--about 6 em deep and 10 em to each side plots (84% survival) were superior to mulched of the trees. All seedlings, except those in plots (64% survival) for the July planting. one of the controls, were protected from rodents Fertilization significantly decreased seedling with a lightweight polypropylene mesh (6 mil) survival within each planting date. Respective that was much less rigid than the 50 mil mesh survivals for fertilized versus unfertilized tubes used at Raton and which could be cut to plots were 22% versus 88% for May. 62% versus the desired length and attached to the trees 86% for July, and 3% versus 95% for August. before planting. At the Grants site, the TSP-only or 10.1 g Results were as follows: At the Raton'site, July Osmocote + TSP treatments applied with mulch planting resulted in the highest survival (73%) were superior· (p

SURVIVAL (%) Revegetation studies showed that containerized seedlings can be planted with satisfactory to 100 excellent success on spoil banks. Planting date was significant at Raton indicating that 80 seedlings should be planted in time for root 60 growth before ground freeze. In a similar study conducted near Gallup, New Mexico at a lower 40 elevation (2,070 m) and latitude, August 20 planting was superior to September and November (Fisher and others, in press). Although the o optimum planting time will vary with site, Raton MAY JULY AUG. and Gallup results clearly show that high survival can be achieved if the June drought is PLANTING DATE avoided. • Mulch / Fert. ~ Drip/ Fert• Dryland plantings in arid regions require some e Mulch / No Fert. Cl Drip/No Fert. method, like organic mulching, to conserve soil Figure 5--Survival percent for ~. monosperma moisture. Mulch clearly improves survival and seedlings planted at Raton. For each planting without severe drought may produce results date, treatment values with the same letter are equivalent to irrigation. not significantly different (p<0.5).

297 Fertilization can provide a benefit, especially Carpenter, S. B.; Graves, D. H.; Kruspe, R. R. if combined with irrigation. Fertilizer should Individual tree mulching as an aid to the be applied in shallow pockets near the tree, not establishment of trees on surface mine spoil. directly into the planting hole. Rec1am. Rev. 1:139-142; 1978. Seedling protectors are essential for success on Djavanshir, K.; G. H. Fechner. Epicotyl ahd sites where rodent populations are substantial.· hypocotyl germination of eastern red cedar The lighter weight, smaller guage (6 mil) mesh and Rocky Mountain juniper. For. Sci. used at the Grants site is recommended over 22:261-266; 1976. rigid 50 mil tubes because the mesh is less expensive, can be attached before going to the Djavanshir, K.; H. Pourbeik. Germination field, stays in place longer and photodegrades value--a new formula. Silvae Genetica in about 1 year. Twelve mil mesh is available 25:79-83; 1976. and would extend protection beyond 1 year. Fisher, J. T.; Fancher, G. A.; Neumann, R. W. In summary, we are confident that use of the Survival and growth of containerized native germination and revegetation practices developed juniper on surface-mined lands in New Mexico. can be joined with existing seedling production Forest Ecol. Manage.; (in press). technology to successfully restore disturbed or over-exploited juniper woodlands. In addition, Garcia, G. A portable irrigation system for it is probable that denuded and severely eroded remote sites. USDA For. Servo Res. Note juniper lands in other countries (for example RM-374; 1979. 2 p. Pakistan) could be restored through similar techniques. Griswold, G. B. Open-pit uranium m1n1ng in New Mexico, In: Survey of Surface Mining in New Mexico: Circ. 114: State Bur. Mines Min. ACKNOWLEDGMENTS Res.; 1971: 8-10.

We gratefully acknowledge technical and Hodder, R. L. Surface-mined land reclamation financial assistance provided by Dr. Earl F. research at Colstrip, Montana. Montana Aldon and the Rocky Mountain Forest and Range Agric. Exp. Stn. Res. Rept. 69; 1974. Experiment Station. Funds were received through USDA Forest Service Cooperative Agreement No. Jensen, N. E. Pinyon-juniper woodland RM-81-173-CA. We are also grateful for the management for multiple use benefits. J. cooperation and support of Kaiser Steel Range Manage. 25:231-234; 1972. Corporation and Pittsburg and Midway Coal Company. Special thanks go to John B. McRae. Johnsen, T.N •• Jr. One-seed juniper invasion of formerly of NMSU, for his dedication and northern Arizona grassland. Ecol. Monogr. conscientious hard work. 32:187-207: 1962. Johnsen. T.N., Jr.; Alexander, R. A. Juniperus REFERENCES . L. juniper. In: Schopmeyer, C. S., ed. Seeds of woody plants in the United States. Aldon, E. F. Reclamation of coal-mined land in USDA For. Servo Agric. Handbook 450; 1974: the Southwest. J. Soil Water Conser. 460-469. 33:75-79; 1978. Lang, P. Reclamation of strip mine spoil banks Aldon, E. F.; Springfield, H. W. Revegetation in Wyoming. Wyoming Agric. Expt. Sta. Res. of coal mine spoils in New Mexico: a J. 71; Univ. of Wyoming; 1971. 32 p. laboratory study. USDA For. Servo Res. Note RM-245; 1973. 4 p. Lanner, R. M. The eradication of pinyon-juniper woodland: Has the program a legitimate Balzer, J. L. A venture into reclamation. purpose? Wes. Wildl. 3:12-17; 1977. Mining Congr. J. 64:24-29; 1975. O'Brien, J. V. Treatments affecting the Barton, L. V. Germination of seeds of Juniperus germination of New Mexico Juniperus virg1n1ana L. Contrib. Boyce Thompson Inst. monosperma seed. Las Cruces, NM: New Mexico 16:387-393; 1951. State Univ.; 1980. 87 p. M.S. thesis.

Berg, W. A. Use of soil laboratory analysis in Pack, D. A. After-ripening and germination of revegetation of mined lands. Mining Congr. Juniperus seeds. Bot. Gaz. 71:32-60; 1921. J. 61(4):32-35; 1972. Riffle, J. W.; Springfield, H. W. Hydrogen Campbell, D. L. Plastic fabric to protect peroxide increases germination and reduces seedlings from animal damage. In: Wildl. microflora on seed of several southwestern Refor. Pacific Northwest Symp.: proceedings; species. For. Sci. 14:96-101; 1968. 1968; Corvallis, OR: Oreg. State Univ.; 1969: 87-88.

298 Schubert, G. H. Forest regeneration of arid Van Haverbeke. D. F.: Read, R. A. Genetics of lands. In: Soc. Amer. For. Nat. Conv.: eastern redcedar. USDA For. Servo Res. Pap. proceedings; 1977: 82-87. WO-32j 1976. 17 p.

Short, H. L.; McCulloch, C. Y. Managing Wagner, W. L.; Martin. W. C.; Aldon, E. F. pinyon-juniper ranges for wildlife. USDA Natural succession on stripmined lands in For. Ser. Gen. Tech. Rept. RM-47; 1977. 10 p. northwestern New Mexico. Reclam. Rev. 1 :67-73; 1978. Springfield, H. W. Mulching improves survival , and growth of Cercocarpus transplants. USDA Whitcomb, C. E. Effects of nutrition on For. Servo Res. Note RN-200; 1972. propagation and rate of establishment of purp1e1eaf Ja~anese honeysuckle, (Lonicera j Tinus, R. W.: McDonald, S. E. How to grow japonica 'Purpurea'). Oklahoma Agric. Expt. seedlings in containers in greenhouses. USDA Sta. Res. Rept. P-760: 1977: 66-68. Gen. Tech. Rep. RM-60: 1979. 256 p. Williamson, R. L.; Wangerud, K. W. USDA Forest Service. User guide to vegetation, Reestablishing woody draws on the northern mining and reclamation in the West. USDA Great Plains after mining the first steps. For. Servo Gen. Tech. Rept. INT-64: 1979. In: Adequate reclamation of mined lands: 85 p. proceedings; Billings, MT; Soil Cons. Soc. of Amer. and WRCC-21; 1980. Van Haverbeke, D. F.; Barnhart, M. R. A laboratory technique for depulping juniperus cones. Tree Planters' Notes. 29:33-34; 1978.

299