Indurated sand in the Late Quaternary coastal plain succession of northern Moreton Bay was examined in sand-mine pits, drillcores and the eroded bank of an estuarine channel. Samples show that the cements usually coat grains and partially infill interstitial pores. Distinctive cement habits reflect different constituents that are dominantly kaolinite and amorphous organic-rich complexes. Trace-metal concentrations in the cements are lower than previously reported for soils and estuarine sediments in the study region. Optically stimulated luminescence and thermoluminescence ages of these deposits indicate that pedogenic induration occurs over long periods, up to approximately 90 000 years, with only incipient induration evident in deposits 16 000-2600 years old. However, the rate of induration is far higher in relatively coarse channel fill, in which mineral and amorphous organic-rich cements have precipitated from shallow groundwater that flowed laterally through the deposit. The degree of induration, therefore, is strongly influenced by the original depositional texture and morphology of deposits, with well-indurated gravely channel fill (76 700 +/- 6500 y), at least 2m thick, sitting adjacent to medium-grained sand probably of dune origin, which contains a 30cm-thick induration horizon (98 000 +/- 9900 y).

The impermeable coat of alfalfa (Medicago sativa L.) seed can reduce germination to an extent unacceptable for commercial use. The usual method of increasing germination of lots with high proportion of impermeable or hard seeds, mechanical scarification, can damage seeds. Experiments were conducted to determine the effect of cultivar, year of production and storage conditions on germination and hard seed content in alfalfa. Experiments with four Canadian cultivars indicated a significant effect of cultivar on seed weight, germination and hard seed content in freshly harvested seed. Year of production had a greater influence on these seed traits than cultivar. Under uncontrolled storage conditions, germination of 35 alfalfa synthetics increased and hard seed content decreased with time, although not at the same rate for all synthetics. Storage at 20 °C for up to 64 mo did not significantly decrease hard seed content. At 35 °C, hard seed content decreased continuously for all cultivars (for one cultivar to <5%) after 64 mo. Over 80.5 mo storage at room temperature (22 ± 2 °C), germination increased in a nonlinear fashion. Storing seed in sealed plastic bags at 35 °C delayed seed dehydration and the loss of hard seeds. Levels of nonviable seed were low (<10%), even after storage at 35 °C for 64 mo. Brief (1 min) exposure to liquid nitrogen increased germination of freshly harvested alfalfa seed to >90%. The results indicate that the germination percent of alfalfa can be increased and hard seed content reduced by short exposure to liquid nitrogen or storage at nonlethal high temperatures (35 °C) such that mechanical scarification may be unnecessary. Key words: Medicago sativa, hard seed, stored seed, seed dehydration, high temperature treatment, liquid nitrogen treatment

Six annual legumes were evaluated as components of cereal‐grass‐legume intercrops in two experiments at two sites differing in elevation by 789 m. Barley (Hordeum vulgare L.) and Westerwolds rye‐grass (Lolium multiflorum Lam.) were seeded on all intercrop plots. Dry‐matter (DM) yield, crude protein (CP) and organic matter digestibility (OMD) were measured. DM yield and N content were used to estimate legume N fixation. Experiment 1 was conducted at both sites. At the lower site, Persian clover (Trifolium resupinatum L.) and annual alfalfa (Medicago sativa L.) accounted for 70% of the DM yield in harvest 1 (July), increased CP and OMD, but did not affect intercrop yield. They increased harvest 2 (August/September) intercrop yield by 263% and CP concentration by 65 g kg−1 DM. They increased harvest 3 (October) yield by 275% and CP concentration by 78 g kg−1 DM. Inclusion of striate lespedeza (Lespedeza striata) did not affect intercrop yield or quality. Annual legumes failed to establish at the higher elevation site and therefore had no effect on DM yield or forage quality. In Experiment 2, in which the performance of Westerwolds ryegrass was also compared with that of Italian ryegrass, and conducted at the lower site only, Persian clover and berseem clover (T. alexandrinum L.) increased CP of all three of the year's harvests. These two species contributed 29% of the DM yield in the first harvest (July) but did not affect total intercrop yield. They increased harvest 2 (August) yield by 313%. Persian clover increased harvest 3 (October) yield by 318% and berseem clover increased harvest 3 yield by 405%. Barrel medic (Medicago truncatula) and snail medic (M. scutellata) contributed 29% of harvest 1 yield, and increased both DM yield and CP content. Medics did not regrow. Aubade Westerwolds ryegrass contributed a greater percentage of the DM yield than did Maris Ledger Italian ryegrass at harvests 1 and 2. Ryegrass type did not affect total DM yield but did affect forage quality; intercrops containing the Italian ryegrass had higher CP at harvest 2 and higher OMD at harvest 3 than those containing the Westerwolds ryegrass. Over both experiments, at the lower elevation site, stands with Persian clover, berseem clover or alfalfa produced 80% of the yield of barley‐ryegrass receiving 250 kg N ha−1, and 165% of the yield of unfertilized barley‐ryegrass. Berseem and Persian clover fixed about the same amount of N over the growing season; 188 kg N ha−1 in Experiment 1 and 134 kg N ha−1 in Experiment 2.

Giant wildrye (Elymus cinereus Scribn. & Merr.) plants grown from seed obtained at two altitudes (346, 930 m) were transplanted to two sites (346, 900 m) and observed for 3 yr. Plants from the low altitude source produced more dry matter at both sites. More plants from the low altitude source produced seed heads at the low altitude site but seed head production of plants from the two sources was similar at the high altitude site. Provided studies of germination, seedling establishment and initial growth at different elevations were favorable, seed from low altitude sources could be used indiscriminately for establishing stands of giant wildrye. This would greatly simplify the use of giant wildrye as a forage crop in areas where varying altitude was of concern.Key words: Elymus cinereus, altitude adaptation, growth forms, reciprocal transplants, ecotypes

Summary Following a winter with low temperatures during a period with no snow cover, lucerne (alfalfa; Medicago sativa L.) plants were dug from the field and various root and crown lesions were identified and rated according to severity. The plants were then put into pots of soil and grown for 6 weeks to determine if they would live or die. The relationship between lesions present at the time of digging and survival was then studied to see if the lesions could be used to predict survival. Injuries to several characteristics were found to be associated with plant death: bud vigour, leaf vigour, resistance of root bark to peeling, resistance of root to squeezing, root interior colour and, depending on site, the presence of fungi on the root surface. A model combining injury ratings for three characteristics (bud vigour, root colour, and root resistance to peeling) was developed and survival probabilities based on this model are presented. Use of this model will allow for an early evaluation of low-temperature injury without having to wait for aerial growth to occur.

Pinegrass (Calamagrostis rubescens Buckl.) plots which had been clipped for 4 consecutive years were left to recover for 6 yr. Full recovery did not occur during this period. There was an apparent lag of 1 yr after which recovery proceeded exponentially. Full recovery was estimated to require a minimum of 7 yr following clipping to a stubble height of 15 cm, 13 yr after clipping to a stubble height of 10 cm and 20 yr after clipping to a stubble height of 5 cm.Key words: Calamagrostis, tillers, range, Douglas-fir zone

The effects of intensive herbage removal by either grazing or clipping on yield of pinegrass (Calamagrostis rubescens Buckl.) the following year were compared. Both treatments had a similar effect on the subsequent year yield of pinegrass. During the season of treatment, grazing stimulated new tiller production whereas clipping did not. This new tiller production may partially compensate for the fact that grazing removes additional herbage owing to pull-up. In 1 of 2 yr, grazing on about 1 June caused less stand deterioration than grazing near 1 July or 1 Aug.Key words: Pinegrass, herbage removal, tiller, grass, tillering, total nonstructural carbohydrate

Methods for simple and rapid evaluation of frost damage in plants are limited. A method to evaluate viability following freezing that is applicable to leaves of cyanogenic plants is described. The method involves the change of color of a paper disc impregnated with alkaline picrate from yellow to orange‐brown, owing to reaction with hydrogen cyanide (HCN) released from injured leaves. All leaves and leaflets of birdsfoot trefoil (Lotus corniculatus L., cv. Leo) released, HCN following freezing injury and had similar LD50 values. Leaves that will produce about the same amount of HCN can be obtained near the middle of a plant. Results obtained with this qualitative HCN test were similar to results obtained with existing tests of viability. The main advantages of this test are that it does not expose the plant material to an unnatural situation, and that it allows for more killing temperature measurements for a given labor investment.

Percent total nonstructural carbohydrate (TNC) was measured in rhizomes plus roots of pinegrass (Calamagrostis rubescens Buckl.). The influence of connecting rhizomes on % TNC was evaluated by comparing results from sods with severed rhizomes to results from sods with intact rhizome connections. Severing rhizomes had no effect on % TNC of rhizomes plus roots of nonclipped sods. However, for clipped sods, % TNC was lower if rhizomes had been severed. Presumably, when rhizome connections are left intact, surrounding nonclipped tillers translocate carbohydrates to rhizomes plus roots of clipped tillers within a sod. This result has important implications in the grazing resistance of pinegrass. Since grazing typically involves an uneven utilization of a grass stand, the ungrazed or lightly grazed tillers should play an important role in maintaining the overall vigor of a pinegrass stand. A knowledge of carbon translocation within a tiller and between tillers is important in that it gives a range manager a better understanding of the primary production process (Moser 1977). Clipped annual ryegrass (Lolium muliflorum Lam.) tillers import photoassimilate from nonclipped tillers (Marshall and Sagar 1965). In contrast to these results for ryegrass where the plant acts as an integrated unit, little photoassimilate is translocated between tillers of timothy (Phleum pratense L.) (St. Pierre and Wright 1972). However, carbohydrate is transported within a tiller to all aerial parts and to the associated roots. Sosebee and Wiebe (1971) observed that clipping crested wheatgrass (Agropyron desertorum (Fisch.) Schult.) and barley (Hordeum vulgare L.) increased both the amount of import of carbohydrate from unclipped leaves and the proportion allocated to the shoot within the plant. Interestingly, partial defoliation of the exporting (source) leaf increased to total amount of translocation (Sosebee and Wiebe 1971). An increase in the upward to downward ratio of translocation is believed to cause root die-back (Steinke 1969). To increase our understanding of the grazing resistance of pinegrass (Calamagrostis rubescens Buckl.), we conducted a study on the role of rhizome connections on the level of total nonstructural carbohydrate (TNC) stored in rhizome plus roots. TNC is reported Authors are research scientist and technician, Agriculture Canada, Research Station, 3015 Ord Road, Kamloops, B.C., Canada, V2B 8A9. Authors are indebted to Dr. Dee Quinton for critically reviewing an early draft of this note and to Dr. John Hall for advice on statistical analysis. Manuscript accepted July 24, 1984. to play a role in plant vigor (Ward and Blaser 1961, White 1973, and Trlica 1977). A procedure involving severing rhizome connections and measuring rhizomes plus roots % TNC was used. The interpretation of results from such an experiment is not as straight forward as from experiments (St. Pierre and Wright 1972, Sosebee and Wiebe 1971, and Marshall and Sagar 1965) where radioisotopes are used to measure translocation. Nevertheless, the procedure has the advantage of being simple and not requiring expensive equipment. Materials and Methods A 0.2-ha exclosure adjacent to the Poison Creek site (Stout et al. 1980) was fenced in 1978. Within this exclosure, 24 70 X 20-cm plots were marked to accommodate 4 treatments replicated 6 times. The 4 treatments were as follows: (1) rhizomes intact, tillers not clipped; (2) rhizomes intact, tillers clipped; (3) rhizomes severed, tillers not clipped; and (4) rhizomes severed, tillers clipped. Plots for a particular replicate were located close to each other so that soil, aspect, and cover would be similar for all treatments. Twelve of the 24 plots were selected for rhizome severing. The rhizome connections were severed by excavating a 15 cm wide trench to a depth of 15 to 20 cm around each plot. The trench was then filled with soil and covered with forest floor organic matter. Clipping to a 5-cm stubble height was done on 1, 16 and 30 June. On 8 August, sods (entire plot areas) were dug and % crude protein and % TNC of rhizomes plus roots were measured using methods by Stout et al. (1983). Although it is useful to know the total amount of TNC stored, it was not possible to determine this for pinegrass because it was not possible to remove all of the pinegrass roots from the forest soil. In 1979 the experiment was repeated within a new exclosure adjacent to the 1978 exclosure. Clipping and harvesting dates were within 2 days of those used in 1978. The data were analyzed using a three-way analysis of variance (ANOVA), with a random block design. Results and Discussion The ANOVA revealed (at P<0.05) that clipping decreased % TNC, and serving rhizome connections further decreased % TNC of clipped sods (Table 1). Only when the source sink relationship was altered by removing photosynthetic tissue (the clipped treat276 JOURNAL OF RANGE MANAGEMENT 38(3), May 1985 This content downloaded from 207.46.13.114 on Thu, 26 May 2016 06:22:57 UTC All use subject to http://about.jstor.org/terms Table 1. Influence of neighboring pinegrass tillers on the % TNC and % crude protein content of pinegrass rhizomes plus roots. Clipping Rhizome connections' Measurement treatment Intact Severed TNC Not clipped 6.7 6.5 (% of dry wt.) Clipped 4.6 3.5 SE 0.3 Crude protein Not clipped 4.6 4.5 (% of dry wt.) Clipped 4.4 4.4 SE 0.4 'Values are x from 6 plots per treatment and 2 years (1978 and 1979). ment) was the effect of severing rhizome connections revealed (the severing by clipping term in the ANOVA was significant at P<0.05). This rhizome severing treatment effect is not due to a wounding response, or some other factor related to the actual severing of rhizomes, since rhizomes plus roots of nonclipped sods had a similar concentration of TNC whether they were severed or not severed. We propose that clipping decreased the supply of carbohydrate to the rhizomes plus roots connected to the clipped tillers and, therefore, these clipped tillers provided a sink for carbohydrate from the surrounding intact tillers. Where rhizome connections were intact the sink was partially replenished from the adjacent intact tillers. This proposal is consistent with the observation that assimilate is translocated from the main shoot of annual ryegrass to defoliated tillers (Gifford and Marshall 1973). Neither clipping nor severing rhizome connections around sods affected crude protein level (Table 1). It is frequently found that herbage removal causing a decrease in TNC has no effect on protein reserve level (Owensby et al. 1977). Despite the fact that protein level was not altered by clipping in this study, proteins may still represent an important reserve constituent (White 1973). Although this study does not show that carbohydrate can be translocated from one tiller to the aerial part of another tiller, the results have important implications in the grazing resistance of pinegrass. Grazing typically results in a mosaic of stubble heights (Matches 1966). The untouched or lightly grazed tillers of pinegrass left after grazing are likely to play a role in maintaining the overall vigor of a stand. For example, leaving intact tillers on clipped tall fescue (Festuca arundinacea Schreb.) plants increased tillering, regrowth (dry matter), and food reserves (Matches 1966). Even if the pinegrass translocation is mainly to the roots, as for timothy, and not to other tillers, as for annual ryegrass, it will benefit the stand. Since aerial portions of pinegrass tillers do not survive more than one year (personal observations), growth in the spring must depend upon stored reserves in rhizomes and roots. In conclusion, when a pinegrass sod was clipped to create a carbohydrate sink, intact tillers outside the sod appeared to act as a source for this sink and supplied carbohydrate through connecting rhizomes. Thus ungrazed or lightly grazed tillers should play a role in maintaining the overall vigor of a pinegrass stand.

Pinegrass (Calamagrostis rubescens Buckl.) tiller pull-up (removal other than by cropping of an entire tiller or the aerial portion of a tiller) during grazing was quantified. As many as 48% of the tillers were pulled up during only one grazing pass by a cow. Following repeated passes by a cow, up to 75% of the tillers were pulled up. This tiller pull-up can be partitioned into two categories; "uprooted" refers to entire tillers, usually united in a tuft, that are pulled up with rhizome and root tissue still attached. The "torn" category comprises the aerial portions of tillers that are severed at or near the base of the leaf sheath. In the latter case, only the upper three or four leaves are removed, and the shorter scale leaves and vegetative stem are left attached to the rhizome. More tillers are normally uprooted than are torn during grazing.Key words: Calamagrostis, forage, herbage removal, grazing, grass

Nonstructural carbohydrates in storage tissues of pinegrass (Culumugrostis rubescens Buckl.)consist of sucrose, glucose, fructosan, and starch.The predominant polymer is a long-chain fructosan.An acid-extractable structural carbohydrate appeared to be xylan.Total nonstructural carbohydrates (TNC) of rhizome plus root tissue decreased during May, reached a minimum value during late May to early June, increased until late June, remained constant until late August, and then increased until November.The TNC level of crown tissue was low during May and early June and reached a peak during July and again in the fall.The crude protein concentration of rhizome plus root tissues was relatively constant throughout the season.Rhizome plus roots accumulated the largest amounts of TNC and crude protein.

Pinegrass (Calamagrostis rubescens Buckl.) plots were clipped for four consecutive years, and the effect on vigor was evaluated by counting tiller number∙m−2. Stand vigor, the potential of the pinegrass to produce tillers in a unit area of ground, decreased with successive years of biweekly clipping to a height of 5 cm or 10 cm. Clipping to 15 cm did not significantly affect stand vigor. Clipping intensities could be characterized by the time (t½) required for the number of tillers to decrease by half: t½ = 1 yr for 5 cm clip; t½ = 3.7 yr for 10 cm clip; and t½ = 7.8 yr for 15 cm clip.

Cold-acclimated twigs of Amelanchier alnifolia Nutt. released less HCN at -4.5 C than nonacclimated twigs following slow freezing to -25 C or rapid freezing to -78 C. Cold-acclimated twigs frozen slowly to -25 C released more HCN than cold-acclimated twigs frozen only to -4.5 C. Cold-acclimated twigs frozen slowly to -25 C and then rapidly to -78 C released less HCN at -4.5 C than cold-acclimated twigs frozen rapidly to -78 C. In general, K(+) efflux and the inability to reduce triphenyl tetrazolium chloride following freezing and thawing paralleled HCN release at -4.5 C. Because low K(+) efflux and high triphenyl tetrazolium chloride reduction are known to depend upon membrane integrity, the increased K(+) efflux and the decreased triphenyl tetrazolium chloride reduction following freezing and thawing provide indirect evidence that HCN release at -4.5 C is a measure of membrane damage in frozen cells.

Pinegrass (Calamagrostis rubescens) was clipped at several frequencies and intensities at three sites in the Douglasfir (Pseudotsuga menziesii) zone of British Columbia. The effect of herbage removal on pinegrass vigor could be assessed by measuring tiller height, tiller number/mz, or yield/m2 the year following clipping. Variability in pinegrass cover at a site necessitated measuring initial plot cover so than an analysis of covariance could be done to statistically isolate its effect. Initial pinegrass cover did not affect the tiller height measurement however. Plant vigor decrease due to herbage removal depended upon the degree and time of herbage removal and either the environmental conditions during the year of clipping or plant history before herbage removal or both. Pinegrass vigor was most sensitive to clipping during the last half of July and early in August. This is the time when pinegrass growth is slowing down and summer dormancy is setting in. It is recommended that pinegrass be grazed for a short time while it is actively growing (early in June) and then later when mid-summer dormancy is well established (August) to maintain its vigor. If pinegrass must be grazed during July, then it should be rested during July the following year. Further work is required to establish grazing schemes that will maximize animal production and maintain adequate pinegrass vigor.