Climax Timothy Research Articles

Comparison of the National Research Council-2001 Model with the Dutch System (DVE/OEB) in the Prediction of Nutrient Supply to Dairy Cows from Forages

The objective of this study was to compare the DVE/OEB system (DVE = truly absorbed protein in the small intestine; OEB = degraded protein balance) and the NRC-2001 model in the prediction of supply of protein to dairy cows from selected forages: alfalfa (Medicago sativa L. cv. Pioneer and Beaver) and timothy (Phleum pratense L. cv. Climax and Joliette). Comparisons were made in terms of 1) ruminally synthesized microbial CP, 2) truly absorbed protein in the small intestine, and 3) degraded protein balance. In addition, the effects of variety and cutting stage of the selected forages on the potential nutrient supply to dairy cows were also studied. The results showed that the predicted values from the DVE/OEB system and the NRC-2001 model had significant correlations with high R (>0.96) values. However, using the DVE/OEB system, the overall average microbial protein supply based on available energy was 12% higher, and the truly absorbed protein in the small intestine was 15% lower than that predicted by the NRC-2001 model. The difference was also found in the prediction of the degraded protein balances, which was 11% higher based on data from the NRC-2001 model. These differences are due to considerably different factors used in calculations in the two models, although both are based on similar principles. This indicates that a further refinement is needed for a modern protein evaluation and prediction system. In addition, this study showed that the two alfalfa varieties studied (Pioneer vs. Beaver) had no effect, but cutting stage had a profound influence on ruminally synthesized microbial CP (93, 96, 86 g/kg DM at stage of early bud, late bud, and early bloom, respectively) and truly absorbed intestinal protein predicted by the DVE/OEB system (80, 79, 67 g/kg DM at stage of early bud, late bud, and early bloom, respectively). With timothy, both variety (Climax vs. Joliette) and cutting stage had significant impacts on the potential protein supply predicted by both models. The potential protein supply (DVE or MP) to the dairy cow from Climax timothy was higher than that from Joliette timothy (DVE: 46 vs. 32 g/kg DM; MP: 61 vs. 38 g/kg DM). With increasing stage of cutting, the potential protein supply (DVE or MP) was reduced (DVE: 53, 39, 25 g/kg DM; MP: 62, 51, 36 g/kg DM at stage of joint, prebloom head, and full head, respectively).

Hay composition, and intake and digestibility in sheep of newly introduced cultivars of timothy, tall fescue, and reed canarygrass

A 3-year experiment was conducted to compare the nutritive values of early maturing (Climax) and late maturing (Farol) cultivars of timothy ( Phleum pratense L.), low endophyte cultivars of tall fescue ( Festuca arundinacea Schreb.) (Kenhy and Johnstone), and low alkaloid cultivars of reed canarygrass ( Phalaris arundinacae L.) (Palaton and Vantage), on the basis of hay composition, and intake and digestibility in sheep. In each year, primary growth and regrowth of a cultivar were harvested as hays, and each was fed to four Dorset wethers for determining voluntary intake of dry matter (DM) over 10 days and apparent digestibility of DM over 5 days. Averaged across all cultivars, first-cut hay contained less total N and more acid detergent fiber (ADF), intake was lower but was digested better than second cut hay. Cutting cycle did not affect neutral detergent fiber (NDF) content in hay. Among first-cuts, total N content was least in Farol timothy and highest in Vantage reed canarygrass, NDF content was least in Kenhy tall fescue and highest in Farol timothy, and ADF content was low in Farol timothy and Palaton reed canarygrass versus high in Climax timothy and Kenhy tall fescue. Among second cuts, total N content was least in Kenhy tall fescue and highest in Climax timothy and Vantage reed canarygrass, and NDF content was least in timothy cultivars and highest in Johnstone tall fescue and Vantage reed canarygrass. Voluntary intake of DM in sheep was highest for tall fescue (954 g day −1), least for reed canarygrass (798 g day −1), and timothy intake was intermediate (856 g day −1) ( P < 0.05). Apparent digestibility of DM was not different between tall fescue cultivars at first (925 g kg −1) or second cutting (983 g kg −1). First-cut Climax was better digested than first-cut Farol (661 vs. 599; SE 4.0 g kg −1 DM) but digestibility ranked in reverse order for second-cut cultivars (630 vs. 650; SE 4.0 g kg −1 DM). First-cut cultivars of reed canarygrass were equal in apparent digestibility (638 g kg −1 DM) but second-cut Palaton was better digested than second-cut Vantage (605 vs. 580; SE 4.0 g kg −1 DM). Johnstone tall fescue was nearly as high yielding as timothy (7 vs. 7.7 t DM ha −1) and was better utilized than the other grasses.

Hay composition, and intake and digestibility in sheep of newly introduced cultivars of timothy, tall fescue, and reed canarygrass

A 3-year experiment was conducted to compare the nutritive values of early maturing (Climax) and late maturing (Farol) cultivars of timothy ( Phleum pratense L.), low endophyte cultivars of tall fescue ( Festuca arundinacea Schreb.) (Kenhy and Johnstone), and low alkaloid cultivars of reed canarygrass ( Phalaris arundinacae L.) (Palaton and Vantage), on the basis of hay composition, and intake and digestibility in sheep. In each year, primary growth and regrowth of a cultivar were harvested as hays, and each was fed to four Dorset wethers for determining voluntary intake of dry matter (DM) over 10 days and apparent digestibility of DM over 5 days. Averaged across all cultivars, first-cut hay contained less total N and more acid detergent fiber (ADF), intake was lower but was digested better than second cut hay. Cutting cycle did not affect neutral detergent fiber (NDF) content in hay. Among first-cuts, total N content was least in Farol timothy and highest in Vantage reed canarygrass, NDF content was least in Kenhy tall fescue and highest in Farol timothy, and ADF content was low in Farol timothy and Palaton reed canarygrass versus high in Climax timothy and Kenhy tall fescue. Among second cuts, total N content was least in Kenhy tall fescue and highest in Climax timothy and Vantage reed canarygrass, and NDF content was least in timothy cultivars and highest in Johnstone tall fescue and Vantage reed canarygrass. Voluntary intake of DM in sheep was highest for tall fescue (954 g day −1 ), least for reed canarygrass (798 g day −1 ), and timothy intake was intermediate (856 g day −1 ) ( P < 0.05). Apparent digestibility of DM was not different between tall fescue cultivars at first (925 g kg −1 ) or second cutting (983 g kg −1 ). First-cut Climax was better digested than first-cut Farol (661 vs. 599; SE 4.0 g kg −1 DM) but digestibility ranked in reverse order for second-cut cultivars (630 vs. 650; SE 4.0 g kg −1 DM). First-cut cultivars of reed canarygrass were equal in apparent digestibility (638 g kg −1 DM) but second-cut Palaton was better digested than second-cut Vantage (605 vs. 580; SE 4.0 g kg −1 DM). Johnstone tall fescue was nearly as high yielding as timothy (7 vs. 7.7 t DM ha −1 ) and was better utilized than the other grasses.

Effects of nitrogen fertilizer, cutting frequency, and companion legume on herbage production and quality of four grasses

Carlton smooth bromegrass (Bromus inermis Leyss.), Regar meadow bromegrass (B. biebersteinii Roem et Schult.), Climax timothy (Phleum pratense L.), and Oregon commercial meadow foxtail (Alopercurus pratensis L.) were each grown alone or in binary mixture with Peace alfalfa (Medicago sativa L.), Dawn alsike clover (Trifolium hybridum L.), or Cree birdsfoot trefoil (Lotus corniculatus L.) for three production years under three management systems: two cuts with no nitrogen (N) fertilizer; two cuts with 150 kg ha−1 N fertilizer; and four cuts with 150 kg ha−1 N fertilizer. With two cuts per year and no N fertilizer, herbage productivity of each grass was greater when the grass was grown in association with alfalfa than when grown alone, with alsike clover, or with trefoil. With N fertilization, herbage productivity was reduced by cutting more than twice per year, the magnitude of the reduction being smooth bromegrass &gt; meadow bromegrass &gt; timothy &gt; meadow foxtail; yields of smooth bromegrass were almost halved whereas those of meadow foxtail were virtually unaffected, and this effect was consistent for each companion legume treatment. Under conditions of non-limiting soil-N, herbage productivity and N concentration were controlled more by the adaptation of each grass, and its response to frequency of cutting, than by species composition of the seeding mixture. Without supplemental N fertilizer, alfalfa was the most suitable companion legume to enhance the agronomic performance of each of the four grasses. Key words: Forage, nitrogen, cutting frequency, simulated grazing, grass-legume mixtures

The nutritive value for sheep of quackgrass and timothy hays harvested at two stages of growth.

Thirty-two wethers were used to compare the nutritive value of Climax timothy (Phleum pratense L.) and quackgrass (Agropyron repens L. Beauv.) harvested at two stages of maturity, joint and early heading, and fed as hay. Crude protein was higher for quackgrass than for timothy (P less than .01). As maturity advanced, CP decreased (P less than .01), but NDF and ADL increased (P less than .01). Dry matter intake was similar between species but decreased by 8% with increasing maturity (P less than .01). Intake of NDF (g/kg.75) was similar for all hays. With increasing plant maturity, apparent digestibility decreased, the effect being more pronounced for quackgrass. Apparent digestibilities of DM and energy were slightly higher (P less than .06) for timothy, and those of CP and hemicellulose were higher for quackgrass (P less than .01). Apparent digestibilities of NDF, ADF, ADL, crude fiber and cellulose were similar between species. Dry matter intake and digestibility were correlated negatively with the ADL/ADF ratio of the hay (r = -.99, P less than .01), whereas CP intake and CP digestibility were correlated with CP of the hay (r = .99, P less than .01). The Lucas test estimated true protein digestibility at 88.1% and metabolic fecal protein at 29.4 g per kg of DM intake. During the growth trial, DM intake was similar between hays, but ADG of sheep was lower (P less than .01) for those fed hays at early heading vs those receiving hays at the joint stage of maturity. The feed to gain ratio was slightly lower for hays at joint (P less than .08). Under the climatic conditions of the 1988 growing season, the nutritive value of quackgrass was similar to that of Climax timothy.

Responses of forage grasses to aluminum in solution culture

Abstract Growth, nutrient uptake and nutrient uptake efficiency differences in orchardgrass (Dactylis glomerata L.), tall fescue (Festuca arundinacea Schreb), and timothy (Phleum pratense L.) were evaluated at 0, 100, 200, and 300 μM Al. In each of the species, cultivar differences were also compared. In the absence of Al stress, cultivars of orchardgrass outperformed other grasses. The presence of Al reduced shoot and root growth; however, the magnitude of the growth reduction depended upon the species and cultivars. The growth of shoots and roots showed a significant difference with respect to species, cultivars, treatment Al and their Interactions. Aluminum reduced the uptake of many essential nutrients. At 100 μM Al Potomac orchardgrass had the highest and climax timothy had the lowest mineral content. The efficiency ratio (ER) assisted in classifying grass entries into efficient and inefficient utilizers of the absorbed nutrients. The ER is defined as milligrams of dry shoot weight produced per milligram of element in the shoot. The ER for P, K, Cu and Zn gave a positive correlation with shoot weight; however, in general, negative relationships were observed for shoot growth and ER for Mg, Fe, and Mn. In all the species increasing Al concentration from 0 to 100 μM increased ER for Mg and decreased ER for K and Zn. With the exception of tall fescue cultivars, the ER for P was reduced by 100 μM Al. The species and cultivars used in this study showed inter‐ and intraspecific differences in growth, uptake, and ER for nutrients in the presence or absence of Al stress. Significant reduction in growth, even at 100 μM Al by all the three species of grass indicates that these grass species are far more sensitive to Al than the field crops. Therefore, experiments with levels of Al lesser than 100 μM would have given a better outlook on the performances of these grass species.

Comparison of pots versus microcosms for predicting agroecosystem effects due to waste amendment

AbstractTwo laboratory test units (plastic flower pots and intact soil‐core microcosms) were compared for their accuracy in predicting crop yield and element uptake in field plots. All three test units were amended with four treatment levels of unweathered, acidic fly ash (0, 100, 400 and 700 t/ha), fertilized with alfalfa meal and planted in late June with equivalent rates of Saranac alfalfa (Medicago sativa), Climax timothy (Phleum praetense) and Clintford oats (Avena sativa). Microcosms were more accurate than pots in predicting the dose‐response yield curve for alfalfa/timothy grown in field plots. The hypothesis of parallelism between regression equations for alfalfa yield was rejected for pots versus field plots, but was not rejected for microcosms versus field plots. Neither of the two laboratory units accurately predicted the dose‐response curves for oat grain or total oat yield. Pots were only slightly more accurate than microcosms in predicting the enrichment ratios (ERs) for alfalfa uptake of elements from field plots, based on statistical analysis of the distributions of In‐ER ratios for 22 elements. The extra rooting depth of the 60‐cm microcosms may provide more accurate yield data for long tap‐rooted species like alfalfa, as well as permit a second year of accurate data on crop yield and element uptake.

COMPARISON OF POTS VERSUS MICROCOSMS FOR PREDICTING AGROECOSYSTEM EFFECTS DUE TO WASTE AMENDMENT

Two laboratory test units (plastic flower pots and intact soil-core microcosms) were compared for their accuracy in predicting crop yield and element uptake in field plots. All three test units were amended with four treatment levels of unweathered, acidic fly ash (0, 100, 400 and 700 t/ha), fertilized with alfalfa meal and planted in late June with equivalent rates of Saranac alfalfa (Medicago sativa), Climax timothy (Phleum praetense) and Clintford oats (Avena sativa). Microcosms were more accurate than pots in predicting the dose-response yield curve for alfalfa/timothy grown in field plots. The hypothesis of parallelism between regression equations for alfalfa yield was rejected for pots versus field plots, but was not rejected for microcosms versus field plots. Neither of the two laboratory units accurately predicted the dose-response curves for oat grain or total oat yield. Pots were only slightly more accurate than microcosms in predicting the enrichment ratios (ERs) for alfalfa uptake of elements from field plots, based on statistical analysis of the distributions of In-ER ratios for 22 elements. The extra rooting depth of the 60-cm microcosms may provide more accurate yield data for long tap-rooted species like alfalfa, as well as permit a second year of accurate data on crop yield and element uptake.

UPTAKE OF RADIOISOTOPES BY VEGETATION GROWING ON URANIUM TAILINGS

An investigation was carried out on the uptake of several long-lived radioisotopes by grasses growing on uranium tailings. Field plots of creeping red fescue (Festuca rubra L.), reed canary grass (Phalaris arundinacea L.), redtop (Agrostis alba L.) and climax timothy (Phleum pratensis L.) which have been growing for 4 yr were sampled in this study. The tailings and the plant tissue were analyzed for uranium, thorium, radium-226, lead-210 and polonium-210. Sedimentation within the tailings area gave two zones: one of sands and one of slimes. The slimes contained significantly more radium-226, lead-210 and polonium-210 than the sands. There was no difference in uptake behavior by grasses growing in the sands and those growing in the slimes. Creeping red fescue (Festuca rubra L.) showed an anomalous uptake of lead-210, but other than this, all four grass species showed similar uptake behavior. Only uranium and radium-226 were significantly higher in the grasses from the tailings than the control.

EFFECTS OF CUTTING MANAGEMENT ON YIELDS, DIGESTIBILITY, CRUDE PROTEIN, AND PERSISTENCE OF TIMOTHY, BROMEGRASS, AND ORCHARD GRASS

Climax timothy (Phleum pratense L.), Saratoga bromegrass (Bromus inermis Leyss.), and Frode orchard grass (Dactylis glomerata L.) were harvested over a 3-yr period at eight developmental stages of primary growth and aftermath after a 40–64-day regrowth interval. Total dry matter (DM) yields generally increased up to flowering and ranged from 4,370 to 11,840 kg/ha, depending on grass species, cutting management, and season. Aftermath DM rarely exceeded 3,500 kg/ha. The stage of development at initial harvest had only a limited influence on aftermath production. Within the season, orchard grass had a more uniform yield distribution than timothy or bromegrass. The yield distribution of the three grasses was most uniform where the initial harvest was taken at the immature stages of development. Stand persistence was satisfactory under all cutting managements. Per cent in vitro digestible dry matter (IVD) of primary growth ranged from 76.5 to 37.0. In the 2nd and 3rd yr, decline in IVD of primary growth averaged 0.69, 0.66, and 0.82% per day for timothy, bromegrass, and orchard grass, respectively, over a 24-day period. In the 1st yr, this decline was somewhat higher. The IVD of aftermath tended to be higher when the regrowth period was shortest, although this was inconsistent, particularly for timothy and bromegrass. Total digestible DM yields increased up to heading stage. Percent crude protein (CP) of primary growth ranged from 18.2 to 7.1 under various cutting managements and decreased at an average daily rate of 0.33–0.37. Percent CP of aftermath ranged from 15.0 to 9.6. Longer regrowth periods generally resulted in lower percent CP. Cutting management had little effect on average seasonal CP yields.

Effects of Different Initial Cutting Treatments on the Production and Quality of Climax Timothy and Reed Canarygrass1

AbstractTotal yield, aftermath, and total digestible nutrients (TDN) production of perennial grasses when harvested at various physiological stages of development were investigated. The initial harvest of Climax timothy (Phleum pratense L.) and reed canarygrass (Phalaris arundinacea L.) was removed at eight physiological stages of development corresponding to plant heights of 20, 30, 41, 46, 51, 61, 71, and 81 cm.Removal of the initial harvest of timothy when the apical meristem was at a transition stage (plants 30 cm tall) resulted in highest total seasonal yield, aftermath, and TDN/ha. Reed canarygrass, however, produced lowest total seasonal yield and TDN when the initial harvest was removed early, at the first two stages of development. This species was less influenced by initial plant cutting height. Total seasonal aftermath of reed canarygrass varied by only 1,973 kg/ha regardless of when the initial crop was removed. These data indicate a differential response of timothy and reed canarygrass to specific cutting management practices.

SWARD ASSESSMENT OF TEN IRRIGATED PASTURE MIXTURES IN SOUTHERN SASKATCHEWAN

Ten grass-legume mixtures were evaluated for pasture production and growth distribution on irrigated land under high fertility levels. Yearling heifers weighing about 325 kg were used as the grazing animals. A mixture of Troy Kentucky bluegrass, Poa pratensis, and Rambler alfalfa, Medicago media, was the best, followed by a mixture of reed canarygrass, Phalaris arundinacea, creeping red fescue, Festuca rubra, and Rambler alfalfa. Birdsfoot trefoil, Lotus corniculatus, and white Dutch clover, Trifolium repens, proved to be inferior legumes to alfalfa in mixtures because they failed to persist beyond the third year. Carlton bromegrass, Bromus inermis, Chief intermediate wheatgrass, Agropyron intermedium, and Climax timothy, Phleum pratense, displayed poor growth distribution patterns, and the latter two tended to disappear from the stand in the fourth year after seeding.

Studies of Tiller Formation in Reed Canarygrass (Phalaris arundinacea L.) and ‘Climax’ Timothy (Phleum pratense L.)1

The greenhouse and growth chamber experiments reported herein were set up to investigate the influence of the following factors on tillering of ‘Climax’ timothy, Phleum pratense L., and reed canarygrass Phalaris arundinacea L., (a) stage of development at which the first harvest was removed; (b) clipping height; (e) nitrogen level; (d) day‐night temperature; and (e) shading. Stages of development at the time the first harvest was removed were as follows: for Stages 1, 2 and 3 the growing points were 5, 10 and 20 cm, respectively, above the soil surface; Stage 4 was 2 weeks after Stage 3. Tillering was affected as follows by these treatments: Climax timothy plants from Stages 1, 3, and 4 showed no increase in thc number of tillers formed between the 1st and 2nd harvests, but increased thereafter. Tillering under Stage 2 increased between the 1st and 2nd harvests, and declined between the 2nd and 3rd. Plants clipped leaving 10‐ vs 4‐cm stubble showed a 30% increase in the number of tillers formed. Tillering was increased significantly (18%) by the high rate of N (112 vs 28 kg/ha). Reed canarygrass plants clipped at Stages 1 and 2 demonstrated an increase in tillers of 2.6 times between the 1st and 3rd harvests. Those clipped at Stage 3 and 4 performed similarly to the above stages between the 1st and 2nd harvests, but showed no increase thereafter. Plants clipped leaving 10‐ vs 4‐cm stubble produced 26% more tillers. No N treatments were applied to reed canarygrass.The number of tillers formed under high day‐night (32–27C) temperatures was less than the number under the 21–15.5C regime for both species. Climax timothy was more susceptible to injury when subjected to the higher temperature. Both species produced more tiller when shaded (40% of full light intensity received) regardless of whether the day‐night temperature was 32–27C or 21–15.5CDry matter production of reed eanarygrass was approximately equal regardless of whether the first harvest was removed at Stage I or Stage 4, or whether the clipping height was 4‐ or 10‐cm. Climax timothy produced less dry matter when the first harvest was removed at the two earlier stages of maturity, but no difference was found between the 4‐ and 10‐cm clipping heights.

Spring Growth of Reed Canarygrass (Phalaris arundinacea L.) and Climax Timothy (Phleum pratense L.) Under Different Harvesting Systems1

SummaryDuring the spring of 1965 and again in 1966 measurements were recorded at 2‐ to 4‐day intervals on the growth rate of reed canarygrass and ‘Climax’ timothy as influenced by the residual effect of the previous year's treatments. The 1965 results of these treatments were: reed canarygrass — significantly lower rate of growth when clipped at the 4‐cm vs 9‐cm height; Climax timothy — no significant difference. The growth measurements recorded in the spring of 1966 reflected the residual influence on spring growth of clipping height as it interacted with plant maturity at the first harvest. Comparing the 4‐ and 9‐cm clipping heights over the maturity stages showed the following: reed canarygrass — slower growh rate at 4‐ than at 9‐cm heights if the first harvest was removed when the growing point was 5, 10 or 20 cm above the soil (Systems 1,2, and 3), but no difference if 30 cm above the soil or heads had emerged (Systems 4 and 5); Climax timothy — slower growth rate at the 9‐cm height it the first harvest was removed under Systems 2 or 3, but not under the other systems. Considering only the residual effect of the stage of maturity at which the first harvest was removed, harvesting under System 2 was detrimental to growth of reed canarygrass. No significant effect of management system on growth rate was noted for Climax timothy.

Chemical Composition and Nutritive Value of Four Grass Hays and Their Component Parts1

AstractFour first‐growth forages, ‘Sterling’ orchardgrass (Dactylis glomerata L.), ‘Canada common’ and ‘Sac’ smooth bromegrass (Bromus inermis Leyss.), and ‘Climax’ timothy (Phleum pratense L.) were harvested at approximately 50% inflorescence emergence, artificially dried, and fed to dairy goats in total collection digestion trials.Canada common and Sac bromegrass and Climax timothy were separated into headed and nonheaded tillers. Headed tillers were fractionated into an inflorescence portion and by internode into leaf blade, leaf sheath, and stem portions. Nonheaded tillers were divided into leaf blade, leaf sheath, and stem fractions.Sterling orchardgrass was higher than Canada common and Sac bromegrass in the apparent digestibility of dry matter, crude protein, and acid‐detergent fiber; however, there was no difference in dry matter intake. Digestibilities of the two bromegrass varieties were not different. Climax timothy was lowest in digestibility and intake.Top portions of the headed tillers were lower in acid‐detergent fiber and lignin and higher in Kjeldahl nitrogen and in vitro dry matter digestibility than their corresponding basal fractions. Leaf blade, leaf sheath, and stem portions of Canada common bromegrass were generally highest in Kjeldahl nitrogen and in vitro dry matter digestibility and lowest in acid‐detergent fiber and lignin. Sac bromegrass components were intermediate and Climax timothy fractions were lowest in quality. Leaf blades of both headed and nonheaded tillers were generally lowest in acid‐detergent fiber and lignin and highest in Kjeldahl nitrogen and in vitro dry matter digestibility. The reverse was true of the leaf sheaths, while the stems were intermediate.

INFLUENCE OF HARVESTING MANAGEMENT ON YIELD, CARBOHYDRATE RESERVES, ETIOLATED REGROWTH, AND POTASSIUM UPTAKE OF BIRDSFOOT TREFOIL

Empire and Viking birdsfoot trefoil (Lotus corniculatus L.) were seeded in mixtures with Climax timothy (Phleum pratense L.) and harvested for forage according to four management systems: (1) four cuts at pre-bud stage, (2) three cuts at 10% bloom stage, (3) two cuts at 50% bloom stage, (4) two cuts at 75–100% bloom stage. Management 4 produced the most forage in both harvest years. Birdsfoot trefoil root weights were generally higher for the two-cut system than for the three- or four-cut system. Etiolated regrowth from the birdsfoot trefoil roots did not differ significantly due to management m either year. The percent total available carbohydrates did not vary significantly between varieties under the different management systems. Frequent harvesting reduced the forage production of birdsfoot trefoil and the amount of K removed from the soil by the plants.

IN VITRO DIGESTIBILITY OF FORAGE SPECIES AS AFFECTED BY FERTILIZER APPLICATION, STAGE OF DEVELOPMENT AND HARVEST DATES

In vitro digestibility (IVD) and yield of digestible dry matter (DDM) was determined on four forage species; Saratoga bromegrass (Bromus inermis L.), Frode orchardgrass (Dactylis glomerata L.), Climax timothy (Phleum pratense L.) and DuPuits alfalfa (Medicago sativa L.) grown as single species over a 2-year period. Nitrogen and potassium fertilizer in various combinations and rates were applied to these forage species. Two cuttings per season of the various species were harvested. Fertilization with nitrogen and potassium did not affect IVD of grasses at any of the rates applied. The IVD of alfalfa was increased by potassium fertilization, while DDM yield was increased by both nitrogen and potassium fertilization.Each forage species was also harvested at 4-day intervals throughout the season to determine effect of advancing maturity on digestibility. The IVD of the first harvest of forage early in June averaged 77% for the four species, but by late July it had dropped to 58%. Of the four species tested, the IVD of orchardgrass decreased most rapidly while that of bromegrass decreased most slowly.

Effect of Level of Intake and Other Factors on Digestibility of Climax Timothy Hay1,2,3

Two total-collection digestion trials were employed to ascertain the influence of nitrogen fertilization rate, harvest date, and level of intake on the nutritive value of Climax timothy hay. Two plots of timothy were fertilized at two levels of nitrogen per acre, 34.1kg and 56.8kg, respectively. One half of each plot was harvested on June 15 and the remainder on June 25. The four hays were fed to wethers at two levels, limited and ad libitum plus 10% refusal. Intake levels and protein and energy digestibilities were determined for each of the treatment forages.Consistent results were found with respect to: 1) Nitrogen fertilization did not significantly influence forage composition. 2) Harvest date exerted a highly significant difference in forage crude protein content and energy digestibility. 3) Significant differences were found in forage intake levels between harvest dates. 4) The ad libitum feeding rate caused a significant depression in energy digestibility compared to the limited feeding rate.

THE USE OF VERIFICATION TRIALS AS A METHOD OF RATING SEED CLASSES OF CLIMAX TIMOTHY

Verification trials were made of 26 entries of pedigreed Climax timothy seed and two lots known not to be Climax. No significant differences in plant characteristics between entries could be determined in the year of seeding. In the second year significant differences were obtained between ratings based on a summation of maturity, growth form and height scores. The rating system appeared to be reliable in the determination of varietal purity.

The Nutritive Value of Timothy Hay as Affected by Nitrogen Fertilization

Aftermath Climax timothy was fertilized with four levels of nitrogen, 0 (check), 50, 100, and 200 lb. per acre. The dry matter obtained from the 50-, 100-, and 200-lb. levels was, respectively, 2.6, 3.0, and 3.2 times that of the check plot (790 lb. per acre). Ash content of the forage increased slightly with nitrogen application, nitrogen-free extract dropped markedly, gross energy dropped slightly and crude fiber and ether extract remained relatively unchanged. Crude protein of the forage from 0-, 50-, 100-, and 200-lb. levels was 14.0, 15.9, 18.9 and 20.7%, respectively. Apparent digestibility of protein was significantly greater (P<.05) for the 100- and 200-lb. levels than for the check plot. A correlation (r=0.987) between crude protein content and apparent digestibility of protein was statistically significant (P<.05). With increasing nitrogen application the apparent digestibility of nitrogen-free extract was significantly decreased; crude fiber and ether extract digestibility were unaffected, and dry matter and energy digestibility and TDN values were decreased slightly. Digestible energy was significantly lower at the 100- and 200-lb. levels.