Soft Chess (Munz, 1973; McLeod, 1982). The variety mainly used is usually called 'Blando' brome (McLeod, 1982).

Bromus mollis L. (Hitchcock, 1971; Munz, 1973).

The variety mainly used is 'Blando' brome (Slayback, pers. comm.).

Glumes broad, obtuse, coarsely pilose or scabrous-pubescent, the first 3- to 5-nerved, 4-6 mm long, the second 5- to 7- nerved, 7-8 mm long; lemmas broad, soft, obtuse, 7-nerved, coarsely pilose of scabrous-pubescent, rather deeply bidentate, 8 to 9 mm long, the margin and apex hyaline; awn rather stout, 6-9 mm long; palea about three-fourths as long as lemma (Hitchcock, 1971).

In N.E. Victoria, Australia, Flood (1986) conducted five experiments on germination under differing thermal regimes. For seed that are not dormant, and are incubated in the dark, germination was rapid and complete at temperatures from 10°C to 30°C (50°F to 86°F). At 38°C (100.4°F), germination is inhibited. Chilling did not alter germination rate. If seed are incubated in light, pre-chilling to 20°C (68°F) accelerates germination. Prolonged (60h) wetting followed by drying killed the protruding radicle with primary roots emerging from the base of the dead radicle.

The species shows strong seedling vigor (Finch and Sharp, 1983).

Softly pubescent throughout. culms erect, 20-80 cm tall; panicle erect, contracted, 5-10 cm long, or, in depauperate plants, reduced to a few spikelets (Hitchcock, 1971).

Annual, sheaths retrorse-pubescent; blades mostly 2-5 mm wide (Munz, 1973).

Soft chess has been grown at 3200 feet altitude with a minimum temperature of 0 F, however it does not usually survive over 4,000 feet elevation. (Fred Thomas, pers. comm.)

In N.E. Victoria, Australia, Flood (1986) conducted five experiments on germination under differing thermal regimes. For seed that are not dormant, and are incubated in the dark, germination was rapid and complete at temperatures from 10°C to 30°C (50°F to 86°F). At 38°C (100.4°F), germination is inhibited. Chilling did not alter germination rate. If seed are incubated in light, pre-chilling to 20°C (68°F) accelerates germination. Prolonged (60h) wetting followed by drying killed the protruding radicle with primary roots emerging from the base of the dead radicle.

Introduced from Europe, this grass is a common weed in waste places (Munz, 1973). Hitchcock (1971) stated that it is common in Canada, Alaska, and along the Pacific Coast, and occurs occasionally east to Nova Scotia and south to North Carolina. In California it is adapted to all climatic conditions below 3,000 feet (Finch and Sharp, 1983).

Soft chess needs at least 12" annual rainfall (Slayback, pers. comm.).

Soft chess Bromus mollis suppresses broad-leaf filaree (Erodium botrys) by shading more effectively under conditions of adequate sulfur. When sulfur is limited, broad-leaf filaree tends to get access to it sooner because of more rapid extension of its young roots (McCown and Williams, 1968).

Best on soils around pH 7.0 (Slayback, pers. comm.).

Soft chess does well on sandy loam to clay loam soils with good drainage (Slayback, pers. comm.). Will grow on coarse to fine textured soils with good drainage (Finch and Sharp, 1983).

Soft chess does best in full sun (Slayback, pers. comm.).

Soft chess is an annual grass (McLeod, 1982; Slayback, pers. comm.) and is regarded as one of the most reliable reseeding winter annuals available (Finch and Sharp, 1983). Flowering occurs from April to July (Munz, 1973).

In N.E. Victoria, Australia, Flood (1986) conducted five experiments on germination under differing thermal regimes. For seed that are not dormant, and are incubated in the dark, germination was rapid and complete at temperatures from 10°C to 30°C (50°F to 86°F). At 38°C (100.4°F), germination is inhibited. Chilling did not alter germination rate. If seed are incubated in light, pre-chilling to 20°C (68°F) accelerates germination. Prolonged (60h) wetting followed by drying killed the protruding radicle with primary roots emerging from the base of the dead radicle.

Flood and Halloran (1982) collected seed of four winter annual grass species in northeastern Victoria, Australia, and grew two generations of these in the laboratory at two temperatures and two daylengths (factorial). Long photoperiod paired with low temperature promoted flowering in annual ryegrass (Lolium rigidum) and soft brome (Bromus mollis). This sort of induction (vernalization) would postpone flowering beyond winter for plants that germinate in late fall or early winter. A lesser response was observed for squirrel-tail fescue (Vulpia bromioides) and Mediterranean barley grass (Hordeum hystrix).

Recommended seeding rates include 5-10 lbs/acre (Miller et al., 1989) and 6 lbs/acre (Finch and Sharp, 1983). Slayback (pers. comm.) suggested that if broadcast 6 lbs/acre suffices; if drilled, 4 lbs/acre.

Seeding depth should be 1/2 inch (Finch and Sharp, 1983; Slayback, pers. comm.).

Preferred seeding method is to drill, but broadcasting and harrowing is feasible (Slayback, pers. comm.). Glenn McGourty established soft chess and other cover crops in vineyards by discing twice to prepare the seedbed, broadcasting seed, cultipacking, and immediately applying 1 inch of water by sprinkler irrigating (Bugg et al., 1996).

Seeding dates from September through October are optimum (Slayback, pers. comm.), but fall to early winter can also suffice (Finch and Sharp, 1983).

No inoculation is required because this is a grass (Slayback, pers. comm.).

Seed production is good in California, and seed is readily available (Slayback, pers. comm.).

Flowering occurs from April through July (Munz, 1973).

Seed matures about April 15 to May 1 (Finch and Sharp, 1983).

Seed production ranges from 800 to 1200 lbs/acre (Slayback, pers. comm.), and seed can be produced even under intensive clipping if the mower is not lower than 2 to 4 inches (Finch and Sharp, 1983). Early clipping (presumably during winter) promotes tillering and can increase seed production by 30% (Love and Eckert, 1985).

Soft chess stores well. Percent of germinable seed should be assessed after 5 years (Slayback, pers. comm.).

Suberect (Finch and Sharp, 1983; Slayback, pers. comm.) to erect (Slayback, pers. comm.) growth habit.

'Blando' brome attains up to 30 inches on good site (Slayback, pers. comm.), and Munz (1973) wrote that soft chess reaches heights of 20-80 cm, but in a replicated study (r=4) at the Blue Heron Vineyard (Fetzer Vineyards), Hopland, Mendocino County, California, May 2, 1991, cv 'Blando' was measured at 100.9+/-2.2 cm (39.8 +/- 0.9 inches), Mean +/- S.E.M. (Bugg et al., 1996). This vineyard was on highly fertile alluvial soil.

Soft chess has a dense, fibrous root system (McLeod, 1982; Finch and Sharp, 1983).

'Blando' has strong seedling vigor and reseeds if allowed to mature (Slayback, pers. comm.).

'Blando' brome is good at reseeding itself (McLeod, 1982).

Soft chess can be mowed during the growing season to a height of 4". Stop mowing during March or April to allow seed maturation during April or May (Slayback, pers. comm.).

Soft chess can be clipped repeatedly during the growing season, but stop during late March or early April to allow recovery and seed maturation in late April. If mowed no lower than 3 inches. just prior to maturity, some reseeding will take place. To reduce frost threat, it can be clipped at 2 inches without damaging the stand (Finch and Sharp, 1983).

Christensen (1971) wrote that for Californian vineyards, French plowing would leave a narrow strip of cover crops in each alley, and would permit use of early-maturing species like brome grass. Dates for plowing down cover crops depend on the maturation dates: Early May is appropriate for brome grass.

Soft chess is swathed to cull the seed then harvested using a combine. (Fred Thomas, pers. comm.)

Soft chess can be uses as a cover crop, annual range grass, for erosion control on dryland slopes, or food or cover and nesting habitat for wildlife (Slayback, pers. comm.).

This is probably the most adaptable annual grass where winter cover alone is required and is suitable for non-tillage systems or where winter cover is alternated with summer fallow or volunteer summer annuals. It is recommended for orchards and vineyards with non-tillage systems, both with frequent clipping and infrequent clipping (Finch and Sharp, 1983).

Soft chess does not produce much biomass and, therefore, is a viable option for raisin, almond, and walnut growers who need refuse-free drive rows (McKenry, pers. comm.).

Soft chess can be used in mixtures with reseeding legumes, including rose clover and 'Lana' woollypod vetch (Slayback, pers. comm.). Bromus mollis shades out broad-leaf filaree (Erodium botrys) more effectively with adequate sulfur. When sulfur is limited, broad-leaf filaree assimilates it sooner because of more rapid extension of its young roots (McCown and Williams, 1968).

Christensen (1971) suggested winter cover crops for Californian vineyards, with the aim of producing a sod-like condition. Cover crops would be low growing, require little or no mowing, and be self re-seeding. Their functions would be to reduce tillage and dust, provide habitat for predators that attack spider mites, improve water penetration, and provide nitrogen. Annual grasses suggested include barley, 'Blando' brome, or cereal rye. Subterranean clovers recommended include cv 'Geraldton', Dwalganup', 'Howard', and 'Mt. Barker'. Rose clovers included cv 'Kondinin' and 'Hykon'. Medics suggested were California bur clover, Cyprus barrel medic, and 'Harbinger' barrel medic. Mixtures of subterranean clovers were suggested so that better adapted varieties will reseed.

As noted by Blake (1991), cover crops managed without tillage may be important in reducing rill and sheet erosion from hillside vineyards, which if uncontrolled can lead to soil losses of as much as 14 tons/a annually. Mowed 'Blando' brome, 'Zorro' fescue, and resident vegetation were compared to tillage in vineyards on various soils. Shallow clayey soils may predispose for water stress caused by no-till cover crops. On the other hand, cover crops may improve soil porosity in the upper 16" and thereby enhance water availability in deeper soils to a depth of 3 feet. Mowed cover plots were dominated by annual grasses by a ratio of 2:1 over forbs, whereas the reverse was true in tilled vineyard plots. The preponderance of deep-taprooted forbs may explain water depletion in tilled plots. On the shallow clay site, early mowing of 'Zorro' fescue plots may have enabled invasion by a more vigorous annual ryegrass (Lolium temulentum), which may have led to increased water depletion.

Above-ground dry biomass of 'Blando' brome was 9.5 +/- 1.4 Mg/ha (Mean +/- S.E.M.) in a replicated trial (r=4) at the Blue Heron Vineyard (Fetzer Vineyards), Hopland, Mendocino County, California, May, 1991 (Bugg et al., 1996). This is significantly less than biomass obtained for barley ('U.C. 476'). With weeds included, the dry biomass in plots sown to 'Blando' was 9.9+/-1.6 Mg/ha.

Blando brome is not a legume and makes no net nitrogen contribution (Bugg, pers. comm.).

As noted by Blake (1991), cover crops managed without tillage may be important in reducing rill and sheet erosion from hillside vineyards, which if uncontrolled can lead to soil losses of as much as 14 tons/a annually. Mowed 'Blando' brome, 'Zorro' fescue, and resident vegetation were compared to tillage in vineyards on various soils. Shallow clayey soils may predispose for water stress caused by no-till cover crops. On the other hand, cover crops may improve soil porosity in the upper 16" and thereby enhance water availability in deeper soils to a depth of 3 feet. Mowed cover plots were dominated by annual grasses by a ratio of 2:1 over forbs, whereas the reverse was true in tilled vineyard plots. The preponderance of deep-taprooted forbs may explain water depletion in tilled plots. On the shallow clay site, early mowing of 'Zorro' fescue plots may have enabled invasion by a more vigorous annual ryegrass (Lolium temulentum), which may have led to increased water depletion.

'Blando' brome improves soil tilth if incorporated or mowed. (Slayback, pers. comm.).

As noted by Blake (1991), cover crops managed without tillage may be important in reducing rill and sheet erosion from hillside vineyards, which if uncontrolled can lead to soil losses of as much as 14 tons/a annually. Mowed 'Blando' brome, 'Zorro' fescue, and resident vegetation were compared to tillage in vineyards on various soils. Shallow clayey soils may predispose for water stress caused by no-till cover crops. On the other hand, cover crops may improve soil porosity in the upper 16" and thereby enhance water availability in deeper soils to a depth of 3 feet. Mowed cover plots were dominated by annual grasses by a ratio of 2:1 over forbs, whereas the reverse was true in tilled vineyard plots. The preponderance of deep-taprooted forbs may explain water depletion in tilled plots. On the shallow clay site, early mowing of 'Zorro' fescue plots may have enabled invasion by a more vigorous annual ryegrass (Lolium temulentum), which may have led to increased water depletion.

Water infiltration improvement provided by cover crops must be weighed against increased water consumption. In a vineyard field trial, Gulick et al. (1994) compared water use and water infiltration under three regimes: (1) Soft chess (cv 'Blando') cover crop in the winter, followed by summer resident vegetation; (2) Soft chess cover crop in the winter, herbicided to provide dead mulch; (3) Bare soil maintained by herbicide treatment. By the second year, treatment 1 showed 2.5 times the cumulative infiltration of water than treatment 3, with treatment 2 intermediate. Where perched water tables occur, more rapid inflow rates may be needed to avoid anaerobic root conditions in cover cropped vineyards. Where soils have no such limitations, cover crops controlled by herbicides in the spring present a clear advantage in greatly increasing water infiltration at a modest expense and a 19% increase in evapotranspiration.

Livestock readily eat soft chess. It is a major source of high- protein feed in California. It is the best annual grass to seed for annual rangeland feed. (Fred Thomas, pers. comm.)

Wind-blown pollen serves as an alternate food for the arbored predatory mite Euseius tularensis (Ouyang et al., 1992). 'Blando' brome occasionally harbors grain aphids, associated beneficial insects (Bugg, pers. comm.).

McKenry (pers. comm.) reported that 'Blando' brome may sustain development of some Meloidogyne incognita but is generally not a host to Meloidogyne spp. It does not appear to host M. hapla, whereas many legumes do.

Weed above-ground dry biomass in plots seeded to 'Blando' soft chess at Blue Heron Vineyard (Fetzer Vineyards), Hopland, Mendocino County, California, May 15-16, 1991, was 0.4+/-0.2 Mg/ha, Mean +/- S.E.M, which is 8.54% of the weed biomass in control plots. Dominant winter annual weeds were chickweed, shepherds purse, rattail fescue, and an annual ryegrass (probably darnel, Lolium temulentum L.). Vegetational cover by 'Blando' brome was 92.5+/-1.4% (Mean +/- S.E.M.) in early May (Bugg et al., 1996).

Bromus mollis shades out broad-leaf filaree (Erodium botrys) by shading more effectively under conditions of adequate sulfur. When sulfur is limited, broad-leaf filaree assimilates it sooner because of more rapid extension of its young roots (McCown and Williams, 1968).

Blake (1991) noted that cover crops managed without tillage may be important in reducing rill and sheet erosion from hillside vineyards, which if uncontrolled can lead to soil losses of as much as 14 tons/a annually. Mowed 'Blando' brome, 'Zorro' fescue, and resident vegetation were compared to tillage in vineyards on various soils. Shallow clayey soils may predispose for water stress caused by no-till cover crops. On the other hand, cover crops may improve soil porosity in the upper 16" and thereby enhance water availability in deeper soils to a depth of 3 feet. Mowed cover plots were dominated by annual grasses by a ratio of 2:1 over forbs, whereas the reverse was true in tilled vineyard plots. The preponderance of deep-taprooted forbs may explain water depletion in tilled plots. On the shallow clay site, early mowing of 'Zorro' fescue plots may have enabled invasion by a more vigorous annual ryegrass (Lolium temulentum), which may have led to increased water stress.