This form has been termed woollypod vetch (Williams et al., 1959; McLeod, 1982), woolypod vetch (Duke, 1981), and smooth vetch (Hermann, 1960). Duke (1981) considered it a form of Vicia villosa, and thus the names winter vetch, hairy vetch, and sand vetch might also apply.

The species names has been cited as Vicia dasycarpa Ten., Viagg. Abrezz. 81. 1829 (Hermann, 1960), Vicia dasycarpa Ten. (Williams et al., 1959), Vicia villosa ssp. dasycarpa (Duke, 1981; Abd El Monem et al., 1990), and Vicia villosa Roth ssp. dasycarpa Ten. (Bugg, 1992).

Cv 'Lana' was selected and developed at Pleasanton by the Soil Conservation Service Plant Materials Center, USDA, in cooperation with the Agronomy Dept. of the University of California, Davis, from material introduced from Turkey in 1937. The original accession was assigned the number K1924 by the Agronomy Dept. and subsequently numbered P-13910 by the Pleasanton Center. It has been used widely and successfully in California for seeding rangeland (Williams et al., 1959).

'Auburn' and 'Oregon' are other cultivars (McLeod, 1982). Cv 'Auburn' was selected and developed by the Alabama Agricultural Experiment Station as a forage and cover crop and was certified for use in Alabama and California (Williams et al., 1959).

'Lana' was the most recent successful vetch introduced to California (Miller et al., 1989).

Seeds subglobose to oval-oblong, 4 to 5 mm. in diameter, dull blackish brown to velvety black, sometimes obscurely mottled, the hilum encircling about 1/7 of the seed (Hermann, 1960).

Woollypod vetch produces a moderate proportion of hard seed. The seeds are more oval than are the nearly round seeds of hairy vetch (Williams et al., 1959).

'Lana' has strong seedling vigor (Finch and Sharp, 1983).

Hermann (1960) described woollypod vetch as being very similar to hairy vetch ( V. villosa ) but differing in its appressed-pubescent or glabrate stem and foliage, in its fewer (usually only 5 to 15)-flowered racemes not plumose in bud, and in its shorter (1 to 2 mm. long), glabrescent lower calyx-teeth. Distinction is sometimes made between the woollypod vetch ( V. dasycarpa ) and the "smooth hairy" vetch (V. dasycarpa var. glabrescens), a race that was formerly considered a variant of the hairy vetch (V. villosa). In the typical from of the woollypod vetch, the leaflets tend to be obtuse and as much as 4 to 6 mm. wide, the racemes mostly only 6- to 12- flowered and longer than the leaves, the flowers usually less than 15 mm. long, the pods about 40 by 10 mm., often finely hairy. In the smooth vetch, the leaflets are commonly acute and only about 2 to 4 mm. wide, the racemes generally many-flowered and hardly longer than the leaves, the flowers about 15 to 17 mm. long, the longest pods about 9 mm. wide. The two races are connected by numerous intermediate forms, however, so that their separation is often impracticable.

Williams et al. (1959) stated that woollypod vetch is similar in general appearance to hairy vetch; however, the flowers are a little smaller. Woollypod vetch is self-fertile, although very attractive to bees.

Woollypod vetch is tolerant of early frosts, less winter hardy than hairy vetch, but hardier than purple vetch (Williams et al., 1959); where temperatures do not fluctuate widely or there is snow cover, it will stand 0 deg F or lower (McLeod, 1982). Cv 'Lana' has been called resistant to frost (Miller, 1988) yet can grow rapidly during mild winters (Miller et al., 1989). Stands survived the winter of 1990-1991 in the Sacramento area of California, where a severe advective freeze kept temperatures near 13 F for several days (Bugg, pers. comm.). In plantings of cv 'Lana' at the Rodale Institute Research Center (Pennsylvania), most plants did not survive winter (Hofstetter, 1988). Woollypod vetch grows better in cool weather than hairy vetch and is more heat tolerant (McLeod, 1982). Cv 'Lana' performed well in trials at Ontario and Davis where winters are influenced somewhat by the ocean. These trends seem to indicate a slight yield advantage to 'Lana' under coastal influence (Williams et al., 1959). 'Lana' should work in areas where winters are mild but cool, and summers are warm (Hofstetter, 1988). Cv 'Auburn' looked best under the more extreme conditions in the the Central Valley, suggesting a slight yield advantage under more severe interior climatic conditions (Williams et al., 1959).

The forms used in California were introduced from Turkey (Williams et al., 1959). Hermann (1960) mentioned that the species is naturalized in scattered locales from Maine to Montana, south to Georgia, Missouri, and California. Munz (1973) listed woollypod vetch as a native of the Mediterranean region and as naturalized in Marin County of California. It now appears naturalized in much of the Sacramento Valley north of Stockton, as well (Bugg, pers. comm.). Woollypod vetch can grow in all areas of the U.S. during cool, moist weather (McLeod, 1982).

This form requires 10 inches or more annual rainfall and is restricted to elevations below 4,000 feet (Williams et al., 1959). The elevational limit was repeated by Graves et al. (1986) and Miller et al. (1989). Finch and Sharp (1983) wrote that the form is well adapted in California below 3,000 ft.

This form requires 10 inches or more annual rainfall according to Williams et al. (1959). Murphy et al. (1976), by contrast, gives the requirement as 16 inches or more, as echoed by Munoz & Graves (1988)

'Lana' is resistant to waterlogging (Miller, 1988).

Stivers & Shennan (pers. comm.) found that cv 'Lana' under normal rainy winter conditions dried out the soil profile down to a depth of 24 inches relative to a winter fallow. The actual amount of water lost in this drying out of the profile was less than 5 percent of the standard amount of irrigation water used to irrigate the summer cash crop.

Woollypod vetch has a low lime requirement (McLeod, 1982).

On rangelands, fertilizing at time of planting with 200 to 500 lbs/acre of single superphosphate will suffice for the majority of range soils. In areas where sulfur is lacking, 200 to 400 lbs. of gypsum per acre is adequate. Refertilize every two or three years (Williams et al., 1959).

Woollypod vetch is tolerant of moderately acid to moderately alkaline soils, according to Williams et al. (1959); 'Lana' was said by Munoz & Graves (1988) to tolerate neutral to acid soils.

Woollypod vetch is tolerant of moderately acid to moderately alkaline soils, according to Williams et al. (1959) (this was echoed by Murphy et al. (1976) and Graves et al. (1986) as regards moderately alkaline soils); it was said by McLeod (1982) to grow well on any soil, even poor, sandy lands.

Cv 'Lana' was said to tolerate loam to clay soils (Munoz & Graves, 1988), and to be well adapted to all orchard and vineyard soils in California below 3000 ft (Finch and Sharp, 1983).

Woollypod vetch is used successfully in mature walnut and citrus orchards, suggesting some tolerance of shading.

'Lana' woolypod vetch is apparently tolerant of glyphosate herbicide (James Durst, pers. comm.).

Woollypod vetch was listed as annual or rarely perennial (Hermann, 1960). In California, it behaves as a winter annual (Williams et al., 1959); cv 'Lana' starts growing in the fall, puts on most of its growth in early spring, and matures in late May (Finch and Sharp, 1983). This vetch usually makes more growth during the winter and early spring than most vetches (Miller et al., 1989). Nonetheless, cv 'Lana' makes most of its growth is in early spring and matures in late May (Graves et al., 1986).

Suggested seeding rates include 15 lbs/acre of inoculated seed (Williams et al., 1959), 15 lbs/acre (Finch and Sharp, 1983), 15 to 20 lbs/acre (Slayback, pers. comm.), 15 to 25 lbs/acre of raw seed (Graves et al., 1986), 20 lb/acre (Hofstetter, 1988), 25-50 lb/acre for cover crop or living mulch (Munoz & Graves, 1988), 30-60 lb/acre (Miller, 1988), 40 to 60 lbs/acre for rangeland (Miller et al., 1989), 50 to 60 lb/acre (McLeod, 1982), and 56-67 lb/acre for green manure (Munoz & Graves, 1988).

Depth of seeding should be 3/4 inches (McLeod, 1982).

Williams et al. (1959) advised some seedbed preparation, such as disking. Covering the seed, preferably by drilling, will improve the first year's stand. Seed may be drilled or broadcast on a well-prepared seedbed (Finch and Sharp, 1983). Drilling gives better results than broadcasting seed into a prepared bed (Graves et al., 1986).

Cv 'Lana' woollypod vetch should be sown from September-October (Slayback, pers. comm.), in early fall (Munoz & Graves, 1988), or in the fall (Finch and Sharp, 1983). October is the best month, according to Williams et al. (1959), who stated that midwinter plantings are likely to be only moderately successful, even during mild winters.

The appropriate rhizobia is inoculant type "C" (same as for other vetches and field pea, Nitragin Co.) (Burton and Martinez, 1980; Munoz & Graves, 1988).

Cv 'Lana' seed is widely available (Slayback, pers. comm.).

Woollypod vetch is the earliest-maturing species of commercially available vetches, blooming about three weeks earlier than purple vetch (Williams et al., 1959). Miller et al., (1989) echoed this, writing that Cv 'Lana' flowers about three weeks earlier than purple vetch and can, therefore, set seed in dryland conditions that would be unfavorable to other vetch species. In Yolo County, California, fall-seeded woollypod vetch is in full flower by mid-April (Bugg, pers. comm.).

Woollypod vetch is the earliest maturing species of commercially available vetches, blooming about three weeks earlier than purple vetch (Williams et al., 1959). Woollypod vetch matures earlier than hairy vetch (McLeod, 1982), and cv 'Lana' is counted the earliest-maturing vetch, with seed ripened by late May (Finch and Sharp, 1983; Graves et al., 1986). It is the only variety that matures early enough to adjust to a short rainfall season (San Diego County) (Graves et al., 1986).

Williams et al. (1959) advised that for seed production, one should plant woollypod vetch at 5 lbs/acre with 5-foot row spacing. It is a prolific seed producer, but shatter creates a harvest problem. Good seed recovery can be obtained by raking the field with a dump or sulky rake without mowing if the stand is heavy enough, otherwise mow and then rake. After the crop has cured in the windrow, combine with a belt-type rubber pickup attachment. Direct combining is possible where the crop has matured uniformly and weather conditions are right. Cylinder speeds of 4000 to 4500 feet per minute and cylinder spacing of 1/4 to 1/2 inch are recommended. Miller et al. (1989) reiterated that for cv 'Lana' seed production is prolific, but that pods are prone to shattering.

Woollypod vetch has been grown for seed in California and Western Oregon (McLeod, 1982). Finch and Sharp (1983) noted that cv 'Lana' requires a regrowth period (without mowing) of about 4 weeks before the late May maturity date in order to produce seed for the next year. This was reiterated by Graves et al. (1986).

'Lana' can maintain self-reseeding stands (Munoz & Graves, 1988).

In Syria, rainfed woollypod vetch yielded 1.26 and 1.14 Mg/ha of seeds in separate trials (Abd El Monem et al., 1990).

Abd El Monem et al. (1990) found that in Syria, rainfed woollypod vetch attained maximum biomass yield at 20-50% podding. By contrast, common vetch attained maximum biomass at maturity.

The seed remains viable for a relatively long time (McLeod, 1982).

Woollypod vetch is more prostrate in growth habit than purple vetch (Williams et al., 1959). Cv 'Lana' is semiprostrate with trailing stems (Finch and Sharp, 1983; Graves et al., 1986), and is very viney (Munoz & Graves, 1988). The viny and succulent growth often constitutes a matted carpet two feet deep by springtime (Miller, 1988).

Based on replicated trials in Mendocino wine vineyards, cv 'Lana' shows a great tendency to climb (much greater than for purple or common vetch) and is, therefore, probably unsuitable in most vineyards (Bugg, pers. comm.).

In a replicated study (r=4) at the Blue Heron Vineyard (Fetzer Vineyards), Hopland, Mendocino County, California, May 2, 1991, cv 'Lana' attained a height of 67.31+/-4.21 cm (Mean +/- S.E.M.). This contrasted to 54.61 +/- 3.02 for common vetch and 57.15 +/- 4.46 cm for purple vetch but was not deemed significantly different from these values in the overall assessment of 30 cover crops (Fisher's protected least significant difference = 16.694) (Bugg et al., unpublished data). Cv 'Lana' can become 24 inches tall in a dense stand (Finch and Sharp, 1983; Graves et al., 1986) or 30 inches without support (Slayback, pers. comm.), but when used as a covercrop, it seldom attains its maximum height before being plowed under (Miller et al., 1989).

Woollypod vetch has a taproot-dominated root system (Bugg, pers. comm.).

Kutschera (1960) reported that woollypod vetch generally roots to a depth of 80 cm.

Woollypod vetch is easy to establish (Williams et al., 1959; Finch and Sharp, 1983).

Williams et al. (1959) recommended that on rangelands where there is competition from annual grasses or sprouting brush, newly planted woollypod vetch stands should be grazed as soon as competitors are of pasturable height. Grazing should be to a uniform height of about 3 inches and should last no more than 1 month. Avoid grazing while the soil is saturated, or trampling damage may occur. Remove stock well before spring moisture depletion to allow the vetch to regrow and mature a seed crop. A weed-free brush burn planting becomes better established if stock are kept off the first season until seed is ripe.

In a Pennsylvanian trial, 'Lana' germinated well, but spring regrowth was slow and suppressed by weeds (Hofstetter, 1988).

In vineyards, cv 'Lana' vetch can present a maintenance problem by aggressively climbing trellises (Miller et al., 1989).

Cv 'Lana' reseeds well (Finch and Sharp, 1983), but under no-till management in an organic vineyard in Mendocino County, California, Bugg et al. (unpublished data) found little 2nd-year regeneration after a heavy seed crop the first year. This may relate to hardseededness of the species.

In his organic walnut orchards, Russell Lester of Solano County California (near Winters, Yolo County) is experimenting (1990-1992) with strip management of 'Lana' vetch and other cover crops. In theory, 10% of the orchard floor devoted to a reseeding remnant strip could more than suffice for reseeding the entire floor to cv 'Lana.' Lester uses flail chopping in late April over most understory vegetation. Remnant strips may have to be shifted from year to year to distribute the seed bank (Bugg, pers. comm.).

Finch and Sharp (1983) stated that cv 'Lana' is well suited where mowing is infrequent. Infrequent clipping can occur up to about March 25. The stand should then be allowed to mature until about May 25. It can be mowed during the growing season with the mower height at ca 5 inches. In lieu of mowing, height can be controlled by running a roller or similar implement over the stand.

Miller et al. (1989) cautioned that cv 'Lana' is not tolerant of frequent mowing and can only be mowed down to a height of five inches. Where frequent, close mowing of the cover crop is needed to reduce the threat of frost, 'Lana' vetch will not reseed.

Cv 'Lana' can be mowed after seed production, if reseeding is desired (Munoz & Graves, 1988).

Cv 'Lana' used as a living mulch should be mowed at the time of planting the vegetable (Munoz & Graves, 1988).

Weedy fields of a high 'Lana' vetch can be mowed or grazed very close to the ground for weed control. The vetch will recover and may be quite competitive with remaining weeds. (Mark van Horn, pers. comm.)

Cv 'Lana,' like other cover crops, should be turned under at flowering when used for green manure (Munoz & Graves, 1988).

Goar (1934) wrote that vetch is best cut for hay when cut in full bloom. Vetch leaves dry much faster than the stems. Therefore, handle the hay rapidly in the field, to avoid loss of leaves by shattering. One day in the swath usually suffices, then the hay is cured in shocks.

Bugg (pers. comm.) noted that power spaders (e.g., those manufactured by Celli) are useful for immediate incorporation when soil is moist and with minimal resultant compaction. Heavy disk harrows may otherwise be needed, but these can be more damaging to soil. For mowing, flail choppers give the finest comminution but have less range of adjustment and may mow too close to allow regrowth. Sickle-bar mowers may be workable only when the vetch has twined up a cereal companion crop and is dry. Rotary mowers give a greater range of adjustment than flail mowers; residue is left coarse, however.

Woollypod vetch can be used for forage, cover crops, and green manure (McLeod, 1982; Munoz & Graves, 1988). Cv 'Lana'can be used as living mulch for orchard, vegetable, and cereal cropping systems (Munoz & Graves, 1988).

Williams et al. (1959) suggested that, as a cover crop, it may substitute for purple vetch, as it has outperformed the latter in several trials involving planting at a wide row spacing. The relative price of seed may influence the choice.

Woollypod vetch is the preferred vetch for range seeding purposes; 'Lana' vetch offers the best nutritive quality and year-to-year persistence (Murphy et al., 1976). It makes good hay either alone or in mixture with a cereal (Williams et al., 1959).

Vetches are useful as a source of spring feed but even more important as summer dry forage; also, their seeds are fed upon by upland game birds (Murphy et al., 1976).

Cv 'Lana' is suitable in orchards and vineyards (Finch and Sharp, 1983), where a large amount of biomass is needed, but not where more than three mowings are used before April 1 (Finch and Sharp, 1983). It is also very viny and may cause problems in vineyards (Munoz & Graves, 1988).

As indicated by Goar (1934), when grown for hay, silage, or cover crops, vetches and peas are usually sown along with a cereals. Oat is most often used, but rye, wheat, or barley may also be used. The cereal supports the vetch, preventing it from becoming wet and slimy near the ground, and facilitates harvesting. On fertile loamy soils where oat tillers or stools heavily, 10 lbs/acre of oat in mixture with vetch or peas usually suffices. On light soil, or if for other reasons the oat tillers little, seed oat at 15 to 25 lb./acre. If rye is substituted for oat, use 15-25 lbs/acre, according to soil type and the tendency of the rye to tiller. If the cereal and vetch or pea seeds are mixed before planting, stir the mixture often while drilling, to prevent the lighter seed (e.g., oat) from rising in the seed box, and causing an uneven stand. For hay of high feeding value, seed cereal sparingly, with only enough to support the vetch and prevent lodging.

Williams et al. (1959) wrote that when grown for hay, oat is often suggested as an intercrop for vetch because the former supports the latter and facilitates harvesting. The oat variety 'Kanota' begins flowering at the same time the woollypod vetch is in late bloom, and is therefore a desirable companion. These are the most nutritious stages of growth for hay production. Where hay containing dough-stage oat is desired with woollypod vetch, the variety 'Indio' is suggested. The suggested planting rate is 30 lbs. each per acre each of vetch and oat.

As related by Schenk and Werner (1991), various legumes in the tribe Vicieae (peas, lentils, and vetches) contain Beta-(3-isoxazolinonyl) alanine, which is released into soil as a root exudate and apparently is an allelopathic compound. This chemical can cause reduced growth in seedlings of various grasses and of lettuce. Pea was only slightly affected.

In rangeland plantings, woollypod vetch is compatible for planting in mixture with the annual grasses, 'Blando' brome, and annual ryegrass. They may be added singly or in mixture at the rate of 4 lbs. of grass seed per acre (Williams et al., 1959).

Cv 'Lana' and purple vetch are the two most productive winter legumes grown in northern California (Miller, 1988). Cv 'Lana' produced yields of 6000 lbs/acre dry matter when harvested at maximum growth at Davis (Miller et al., 1989), and 9.180+/-0.933 Mg/ha (Mean +/- S.E.M.) by mid-May in a replicated study (r=4) at Blue Heron Vineyard, Fetzer Vineyards, Hopland, Mendocino County, California; weeds were entirely suppressed (Bugg et al., unpublished data).

Abd El Monem et al. (1990) found that in Syria, rainfed woollypod vetch attained maximum biomass yield at 20-50% podding. By contrast, common vetch attained maximum biomass at maturity. Rainfed woollypod vetch (Vicia villosa ssp. dasycarpa) at 102, 118 132, and 145 days after planting (D.A.P.) yielded 2.08, 4.01, 4.34, and 3.69 Mg/ha of dry matter during 1986- 87, and during 1987-88 at 115, 130, 144, and 163 D.A.P. the corresponding figures were 2.58, 4.51, 5.88, and 5.68. To summarize, maximum biomass yields were obtained around 132-144 D.A.P, and those yields were 4.34 and 5.68 Mg/ha (Abd El Monem et al., 1990).

Corn grown following incorporation of cv 'Lana' woollypod vetch showed a yield response equivalent to 200 lbs/acre of fertilizer N in recent experiment at Davis (Miller et al., 1989) and produced yields of 250 lbs/acre nitrogen when harvested at maximum growth at Davis (Miller et al., 1989). Other estimates for 'Lana' include 50-100 lb N/acre (Munoz & Graves, 1988), 50-200 lb/acre (Munoz & Graves, 1988), and 300 lb of nitrogen per acre by the end of April under favorable conditions when planted in October (Miller, 1988).

At plowdown, of cv 'Lana,' available N (in lbs of N/acre) can be estimated by multiplying harvested fresh weight of cover crop from a sixteen square feet (4 x 4 ft.) sample plot by 18 (Miller et al., 1989).

Hu et al. (1997) conducted a replicated field study at the Student Experimental Farm (SEF) and the Sustainable Agriculture Farming Systems (SAFS) Project, U.C. Davis, CA. The study compared carbon and nitrogen transformations following cover crop incorporation on organically vs. conventionally managed Yolo sandy loam (at SEF: coarse-loamy, mixed, nonacid, thermic Mollic Xerofluvent) and Reiff sandy loam soil (at SAFS: coarse-loamy, mixed, nonacid, thermic Mollic Xerofluvent) Chemical characteristics for the oat and woollypod vetch harvested on April 14 and used as cover crops were as follows (±S.E.M., where indicated):

Prior to incorporation of cover crops, soil organic N and soil organic C were significantly higher in organically managed than in conventionally managed plots, both at SEF and at SAFS. These differences were lessened or obscured during the 35 days following incorporation. Microbial biomass C was initially greater under organic management at both sites; again, differences were obscured following cover crop incorporation. Cover crop debris buried in litter bags in the SAFS plots showed more rapid disappearance in organic than in conventional plots.

Mature residue of cv 'Lana' breaks down rapidly (Finch and Sharp, 1983).

If plowed under as a green manure, 'Lana' can reduce crusting and improve emergence of tomato seedlings (Miller, P.R. and Groody, K., L. Stivers, and C. Shennan, pers. comm.).

Hu et al. (1997) conducted a replicated field study at the Student Experimental Farm (SEF) and the Sustainable Agriculture Farming Systems (SAFS) Project, U.C. Davis, CA. The study compared carbon and nitrogen transformations following cover crop incorporation on organically vs. conventionally managed Yolo sandy loam (at SEF: coarse-loamy, mixed, nonacid, thermic Mollic Xerofluvent) and Reiff sandy loam soil (at SAFS: coarse-loamy, mixed, nonacid, thermic Mollic Xerofluvent) Chemical characteristics for the oat and woollypod vetch harvested on April 14 and used as cover crops were as follows (±S.E.M., where indicated):

Prior to incorporation of cover crops, soil organic N and soil organic C were significantly higher in organically managed than in conventionally managed plots, both at SEF and at SAFS. These differences were lessened or obscured during the 35 days following incorporation. Microbial biomass C was initially greater under organic management at both sites; again, differences were obscured following cover crop incorporation. Cover crop debris buried in litter bags in the SAFS plots showed more rapid disappearance in organic than in conventional plots.

It is palatable to livestock when green but, like most vetches, is more so when dry (Williams et al., 1959). Livestock will avoid it when green as it is "bitter" but will readily eat it dry. (Fred Thomas, pers. comm.)

To ensure high protein feed in summer and early fall, postpone grazing of 'Lana' until after the growing season (Murphy et al., 1976).

Cv 'Lana' flowers attract bees (Munoz & Graves, 1988).

Bugg (pers. comm.) noted that pea aphid (Acyrthosiphon pisum) and associated lady beetles (mainly Hippodamia convergens) and lacewings (mainly Chrysoperla carnea) occur on 'Lana' from mid April until maturity; flower thrips (Frankliniella spp.) and associated minute pirate bug (Orius tristicolor) are abundant in flowers. Woollypod vetch lacks extrafloral (stipular) nectaries so is not very attractive to parasitic wasps. Lygus bugs can be abundant.

Koike et al. (1996), in Salinas, CA, conducted greenhouse and field studies testing tansy phacelia, oil seed radish, barley, 'Lana' woollypod vetch, purple vetch, fava (faba) bean, and 'Austrian Winter' field pea for host status vis a vis the fungal pathogen Sclorotinia minor, and for effect on incidence of the associated lettuce drop disease on following crops of lettuce. Phacelia ('Anglia'), 'Lana' woollypod vetch, purple vetch, and 'Austrian Winter' field pea were identified as major hosts in lab and field trials. An additional field trial in a commercial lettuce field, high incidence of lettuce drop was observed in one of two years following tansy phacelia, but was consistently low following cereal rye.

Woollypod vetch smothers out weed competition (McLeod, 1982) with its dense growth and trailing stems (Finch and Sharp, 1983).

Bugg et al.(unpublished data) conducted a replicated study (r=4) at Blue Heron Vineyard (Fetzer Vineyards), Hopland, Mendocino County, California. Cover crops were seeded in late October, 1990 and harvested on May 15-16, 1991. Dominant winter annual weeds were chickweed, shepherds purse, rattail fescue, and annual ryegrass. Plots seeded to cv 'Lana' showed no weed biomass production at all; of the 32 cover crops seeded, this was the only entry with that distinction. Vegetational cover by 'Lana' in early May was 97.50+/-2.50 % (Mean +/- S.E.M.).

Various legumes in the tribe Vicieae (peas, lentils, and vetches) contain Beta-(3-isoxazolinonyl) alanine, which is released into soil as a root exudate and apparently is an allelopathic compound. This chemical can cause reduced growth in seedlings of various grasses and of lettuce. Pea was only slightly affected (Schenk and Werner, 1991).