Nature of Work: Reducing or preventing erosion in riparian areas requires minimal soil disturbance (1). One solution to this problem is to use live stakes which are " . . . woody plant cuttings capable of quickly rooting in the streamside environment. The cuttings need to be large and long enough to be tamped as stakes" which is usually 0.5 to 2 inches in diameter and 2 to 3 feet long. "Stakes are used on streambanks of moderate slope (4:1) in original soil, not on fill." (2)

The objectives were:

1. to evaluate the influence of IBA treatments on the percentage of stakes surviving in this challenging environment.
2. Determine which species are locally adapted to this technique. The site was Codorus loam along a spring and surface runoff fed stream located at the Mountain Horticultural Crops Research Station, Fletcher, NC. Soil was not tilled or fertilized nor was weed or other pest management implemented at any time during the test.
3. Evaluate how far from moist native soil adjacent to a stream can cuttings be stuck before the soil dries out too much to allow a high enough percentage of cuttings to root and what influence does the slope of a streambank have on success. This test was conducted on similar soil but in an east flowing stream adjacent so that cuttings could be stuck on north and south paired slopes.

   Test 1: Stakes of Alnus serrulata, Cornus amomum and Salix nigra were locally collected on DEC 18, 2001 and kept moist. On DEC 19, 2001 stakes were graded for uniformity and cut to length on a table saw. The bottom was pointed and the top cut perpendicular to the stem to facilitate soil penetration and to ensure that proper polarity of the cutting was maintained.

   Immediately after making a fresh cut, IBA treatments were applied. Treatments were a quick dip of K-IBA/water solution at 0, 1250, 2500 or 5000 ppm IBA with 5 stakes per treatment and 3 replicates.

   After IBA treatment stakes were driven into the soil at the test site leaving at least 6 inches of the stake above the soil surface and one at least one node below the soil surface. Stakes were on 6 inch centers with treatments randomized within replicates. Replicates were parallel to the stream such that any soil moisture gradients due to flooding or drought would likely occur within replicates.

   Test 2: Stakes of Acer negundo, Betula nigra, Physocarpus opulifolius, Platanus occidentalis, and Sambucus canadensis were prepared as described previously but not treated with IBA. Twelve stakes per replicate with three replicates were employed in the test. Otherwise procedures were similar.

   Test 3: Procedures and species were the same as for Test 1. Cuttings were inserted into the embankment perpendicular to the slope on either side of the stream. The first cutting was inserted one foot above water level on DEC 20, 2001. The next cutting was inserted two feet above the water, the next three feet, then four and five feet above the water level of the stream. Different species cuttings were placed adjacent to the first, a foot apart. There were five cuttings of each plant at each elevation from the stream in each of three replicates.

   Survival was determined by bud break from these dormant deciduous shrub cuttings. Data was collected on APR 27, 2002, again on JUN 6, 2002 and SEP 4, 2002 for tests 1 and 2, last data collection for test three was AUG 27, 2002.

   Results and Discussion:
   Test 1: The percentage of plants with living foliage in JUN and SEP were lower than those in APR suggesting that some buds broke without a root system to support growth so plants died. No significant difference in the number of stakes with living foliage existed due to treatments (Table 1).

   Table 1. Percentage of stakes with living foliage on September 4, 2002.

   	Plant
   ppm IBA	Alnus serrulata	Cornus amomum	Salix nigra
   0	0	100	100
   1250	0	100	100
   2500	0	87	93
   5000	0	100	100

   Test 2: Many successive weeks without rain occurred during summer 2002 at MHCRS. Betula nigra, Physocarpus opulifolius, Platanus occidentalis and Sambucus canadensis had 47% or greater stakes with living foliage on June 4 (Table 2). There was no living foliage on Acer negundo at that date. By September survival had dropped dramatically, possibly due to drought.

   Table 2. Percentage of stakes with living foliage.

   	Date
   Plant	Apr 27, 2002	Jun 4, 2002	Sep 4, 2002
   Acer negundo	8	0	0
   Betula nigra	72	47	14
   Physocarpus opulifolius	94	94	86
   Plantanus occidentalis	53	56	33
   Sambucus canadensis	53	56	25

   Test 3: No Alnus serrulata survived. Cornus amomum survived in excellent percentages except immediately adjacent to the stream where cuttings were totally submerged during spring high water. Salix nigra survived only on the south facing slope at the two elevations closest to the stream.

   Table 3. Percent of lives stakes with living foliage on August 27, 2002.

   	South Face			North Face
   Ft. above stream	Alnus serrulata	Cornus amomum	Salix nigra	Alnus serrulata	Cornus amomum	Salix nigra
   5	0	67	0	0	100	0
   4	0	100	0	0	100	0
   3	0	67	0	0	67	0
   2	0	67	33	0	67	0
   1	0	67	33	0	0	0

   Significance to the Industry:
   1. There was no benefit to treating live stakes with the concentrations of IBA used in this test.
   2. USDA recommended species Cornus amomum,/i> and Salix nigra survived at greater than 50%. USDA recommended species Acer negundo did not live.
   3. Physocarpus opulifolius survived in high percentages and should be added to suggest species lists for the region.
   4. Betula nigra, Platanus occidentalis and Sambucus canadensis survived in lower percentages, perhaps due to extended dry summer weather. Alnus serrulata did not survive.
   5. Of the three species evaluated for capacity to root in soils further from the stream, only Cornus amomum survived in acceptable percentages.

   Literature Cited:

   1. Sauer, Leslie Jones. I998. The Once and Future Forest. Island Press. Washington, DC. P. 249-251.
   2. USDA- Soil Conservation Service. 1984. Engineering Field Handbook. Washington, DC USDA. 8:7-11.

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