Western Juniper Woodlands Reconnaissance Form


Western Juniper Woodlands Reconnaissance Form

Lost River Ranch, Bonanza, OR.


1. File Data

Project: Western Juniper Harvest Systems Comparisons Proj., Lost River Ranch, Bonanza, OR.

Date: September & October, 1996

By Whom: Larry Swan, U.S. Forest Service (with assistance from Bill Hopkins, U.S. Forest Service, Zone Ecologist)

2. Location Information

Legal: T39S, R11 1/2 E, SE 1/4 of SW 1/4 of Section 22, Northern Geodetic Vertical Datum of 1929

Access: Unit located on private land adjacent to North Poe Valley Rd. Dirt road bisects unit.

Map Ref.: USDI, Geological Survey, Diary Quad, OR. (1985). Scale = 7.5'

Aerial Photos: 7-6-93, BLM, 12 , 6-93-BLCI, 2-16A-6, 7
1990, NRCS, P35, Tract 852

3. General Description

Acres:
Scabrock = 0.8 ac
Low Density Juniper (0-49 trees/ac) = 4.5 ac
Medium Density Juniper (50-99 trees/ac) = 3.8 ac
High Density Juniper (100-150+ trees/ac) = 5.6 ac
Total = 14.7 ac (per NRCS aerial photo)

Elevation: 4,140 ft.

Aspect: Southwest

Slope: 0-5%

Soil Type/ Depth: See soils report (Nicita 1996)
Low Density Stand = Loamy overburden (20 in. deep)
Medium Density Stand = Clay to clay loam
High Density Stand = Lithic, clayey


Rock:
Visible Scabrock = 0.8 ac in NW corner of unit
High Density Stand, Very lithic = 5.6 ac.

Timber:
See acres summary above. Even-aged western juniper overstory, ranging from low density to high density.

Brush: <1% (scattered sagebrush and a few scattered Ribes sp.)

Other: Project site is located on a portion of the west-facing slope of a low-lying peninsula of western juniper woodlands. The peninsula is surrounded on three-sides by irrigated pasture and crop lands. Three small ephemeral drainages are present in the northwest portion of the project site.

4. Stand Data

Site Index (per Sauerwein 1982): 29-33 (medium high to high for medium and high density stand areas)

Site Index Samples

Stand Density Tallest Tree Per 1/5 Acre Plot Age at DBH Index
High Density 43 73 33
Medium Density 45

42

73

80

33

29

*Low Density 38

40

75

73

28

29



*Special Note: Site index not considered valid for low density portion of stand. According to Sauerwein (1982), site index curves were calculated for "well-stocked" stands, "mostly in the 65-100 range, while on higher sites, up to 250 trees per acre were counted". Low density stand in this case averaged 35 trees/acre.

Narrative Description of Overstory/Understory:

Western juniper entirely dominates the overstory, ranging from 25-35 stems/acre in the lowest density area to 120-160 stems/acre in the highest density area. Shrub cover is sparse, consisting of a few big sage brush (Artemesia tridentata) and current (Ribes sp.). A dense carpet of cheat grass (Bromus tectorum) dominates the groundcover. Medusahead (Taeniatherum captu-medusa), a noxious weed, was observed in patches adjacent to the project site and was sparsely present in a small area of scabrock in the northwest corner of the project site. No harvest activities occurred in areas with medusahead.

Juniper canopy cover was estimated from aerial photographs to be less than 10% in the low density area and greater than 60% in the high density area. Juniper reproduction is sparse. Older junipers are present just east of the project site in an area of scab rock, however ages were not determined. Based on previous experience, they appeared to be at least 200 years old.

Previous Logging: None. Very few stumps evident.

Animal Damage: None observed.

Competing Veg.: See "narrative description" above.

Overstory Stand Data: See Table 4: Lost River Ranch Stand Data Summary

  • Species Comp: Western juniper.
  • Age: 77 at DBH; 89 at stump height
  • Ht./DBH Range: Sapling-48 ft.; Sapling-24.7 in.
  • Distribution: Stand is even age; reprod. is scattered and sparse.
  • Density: Scabrock = 125/ac (0-9" DBH; 0-25 ft.)
  • Low Density = 35-49 trees/ac
  • Medium Density = 50-99 trees/ac
  • High Density = 100-150+ trees/ac
  • Growth Vigor:
    • Low Density = 10/20 last 10 years
    • Med Density = 10/20 last 10 years
    • High Density = 8-16/20 last 10 years
  • Pathogens: None observed.
  • Miscel. Comments:
    Stand is even-aged. A few scattered old growth located to east of unit in scabrock. See table labeled "growth samples" for growth history - usually peaks before 50 years and then tapers. A few snags noted in SE corner of unit. No visually obvious reasons for mortality evident.

Understory Stand Data:

  • Species Comp.: Western juniper.
  • Age: Unknown
  • Ht/DBH Range: Seedling/Sprout/Sapling
  • Distribution: Scattered
  • Density: Sparse
  • Growth/Vigor: Growth = Unknown; Vigor = Seemed browsed.
  • Pathogens: None noted.
  • Narrative: Very sparse juniper reproduction, mainly stump sprouts and a few saplings; more reproduction in scabrock in NW portion of unit.

5. Proposed Treatment

Landowner Objectives: Improve forage for cattle and horses, and maintain cover for domestic livestock and wildlife, especially resident deer herd.

Silvicultural Prescription: Seed before harvest operations with dryland pasture mix (lbs/acre?) and thoroughly scarify ground surface after harvest (see attached FAX message from Mike Borman, OSU Range Extension Agent, regarding cheatgrass treatment options).

Remove 60-80% of stand, concentrating on leaving clumps and screening along fence lines. Leave all trees with bird nests or cavities. Concentrate clumps to maximize solar protection and protection from storm track winds from west. Delimb all leave trees to 6 ft. to improve cover access for livestock and deer.

Slash Treatment: Leave scattered clumps and piles for wildlife (2-4/ac) and scatter remainder of slash. Maintain existing heavily-traveled animal trails along fence lines.

Monitoring: Establish series of exclosures with landowner permission, and monitor once per year for seeding success and reestablishment of native species. Establish photo points and record annually in spring. Landowner does not report any immediate plans to graze livestock in area, other than a few horses in the spring and summer. Cattle are fed on peninsula to east during winter months, but do not appear to come into area very often (very few cow plops).

6. Harvest Plan

System: Chainsaw fall; manually delimb on site or skid to central landing and mechanically delimb; remove and scatter slash back onto site.

7. Red Flags

Noxious Weeds: Medusahead observed on peninsula uphill and to east of unit where cattle are fed during winter months; a few sprouts observed in scabrock area in NW corner of unit.

Fence Lines: Protect existing fence lines.

Drainages: Three ephemeral drainages in northern portion of unit - dry during Sept. and Oct.

8. Other Resource Information

Archaeological Sites: None. Only one obsidian flake observed. Small rock wall outside SE corner of unit.

Recreation: None

Wildlife: Resident herd of deer (10-15); large owl (great horned?); lots of small birds and robins feeding on berries; up to 25 deer in area during harvest.

Soils Sensitivity: None expected - lithic and dry.

Boundaries: Well established and marked by fence lines.

9. Unit Layout

Marking: Tried blue paint, but switched to flagging clumps due to difficulty seeing paint under low crowns.

Boundaries: Clearly evident - fence lines to west and north; scabrock to east; road to south.

Sketch Maps: None produced.




Table 4: Lost River Ranch Stand Data Summary - Pre- and Post- Harvest
Bonanza, Oregon
Timing & Stand Density DBH Range (in) DBH Average (in)(1) Height Range (ft) Height Average (ft) Trees/Acre (Live) Volume/Acre (cu ft)(2)
Preharvest
Low Density
Med. Density

High Density

5.0-18.5
9.6-16.7
Sap-20.1
Sap-17.6
Sap-24.7

10.4
13.6
13.0
14.1
11.7

11-38
23-45
Sap-47
Sap-48
Sap-47

24.7
36.4
32.3
38.0
35.8

35
35
60
160
120

220
420
730
1175
810
Summary Sap-24.7 in Avg 12.6 in Sap-48 ft Avg 33.4 ft Avg. 82 Avg 671 cu ft
Post Harvest
Low Density

Med. Density

High Density

13.1-17.4
10.2-18.6
10.2-15.7
5.6-22.9
6.4-14.7
Seed-12.1
10.7-24.7
4.4-16.9
6.7-15.9

15.9
15.5
13.2
14.9
9.6
9.2
14.8
9.9
10.4

35-44
19-41
34-42
20-47
26-48
Seed-40
30-47
28-47
21-50

39.3
33.8
40.0
37.7
37.3
28.3
36.2
36.6
36.5

20
20
15
15
15
45
25
50
40

300
275
173
275
110
155
380
353
298
Summary Seed-24.7 in Avg 12.6 in Seed-50 ft Avg 36.2 ft Avg 27 Avg 258 cu ft

1. Averages for DBH and height do not include seedling/saplings.

2. Cubic-foot tree volume from 12 in. stump to 4 in. top (Chittester and MacLean 1984).



September 4, 1996

To: Larry Swan
From: Mike Borman
Subj: Juniper treatment options

After visiting with Bill Krueger and Lee Eddleman, we have some options to consider. However, recognize that the risk of failure is quite high (>50%). We haven't been on the ground to evaluate soils, potential other vegetation, longevity of cheatgrass on site, etc. You might consider trying more than one option on different parts of the area you have available.

Option 1: If you can wait until spring to do the juniper treatment, cut and scatter in the spring, then bum it all in the fall to get the nutrient flush. This is not a normal recommendation, however, Lee suspects a nutrient deficiency that burning the juniper would help rectify. Then use a half-width rangeland drill to drill in a desired species as late as possible in the fall.

Option 2: If the cheatgrass still has the majority of its seed intact, burn now, drill a desirable species, then do the juniper treatment.

Option 3: If the cheatgrass has dropped most of its seed, use a propane burner to kill the seed on the ground, drill a desirable species, then do the juniper treatment.

Option 4. Thoroughly scarify the ground (to about 2") to bury much of the cheatgrass seed, then drill a desirable species, then do the juniper treatment. If drilling a desirable species is not an option, then broadcast seed and drag over it to get soil coverage.

Recognize that making these recommendations from a distance is risky. Also recognize that the probability of success for achieving a good forage stand iq low given the current cheatgrass, dominance,

Good Luck.

Mike Borman



Growth Samples in 1/20 of an Inch
Years Sample No. 1
(High Density Area)
Sample No. 2
(High Density Area)
Sample No. 3
(High Density Area)
0-10 NA 27 26
10-20 13 45 38
20-30 16 53 37
30-40 21 40 31
40-50 21 28 12
50-60 19 20 17
60-70 NA 10 8
70-80 NA 8 8
80-90 NA 7 8