Panicum Maximum Pasture Research Articles

Population dynamics of the pasture leafhopper complex (Hemiptera: Cercopidae) in brachiaria and mombasa grass

Pasture leafhoppers are considered highly important pests in forage grasses in Brazil due to their widespread occurrence. This insect is one of the most relevant pests in pasture degradation. In order for the control of spittlebugs to be efficient, it is important to know the population behavior of the species of this insect, identify the period of greatest occurrence, as well as the climatic and environmental conditions that favor the development of the pest. Thus, this study aimed to evaluate the population dynamics of spittlebugs, at a quantitative level, in Brachiaria decumbens and Panicum maximum pastures, associating the results with meteorological data from the municipality of Conceição do Araguaia, Southeast Pará. To study the population dynamics of spittlebugs, samples were taken every two weeks, in two types of pastures aged between 5 and 7 years, kept under rotational grazing, with a stocking of 1.5 animal units. The method of monitoring nymphs and adults of leafhoppers was adopted, through walking within the observation area. The level of infestation of spittlebugs in both forage species was evaluated and all results were submitted to analysis of variance by the F test. It was found that the species B. decumbens had a greater number of adults and nymphs when compared to the forage species P. maximum. The population dynamics of spittlebugs occur gradually according to climatic conditions, and the period with not-so-high temperatures (22 ºC to 34 ºC) and good rainfall provide an infestation of this insect pest in the pasture.

Effects of cutting frequency and levels of nitrogen fertilizer on herbage yield of a guinea grass (Panicum maximum) pasture.

The effects of fertilizer-N application and cutting frequency on the herbage yield of Panicum maximum pasture were investigated in 2001 through 2004 in a sandy loam soil at Nsukka. The experiment was a 4r 4 factorial arrangement laid out in a randomized complete block design with three replications. Treatments comprised four levels of Nitrogen of 0, 150, 300, and 450 kg N ha' and four harvesting frequencies of 3-6-19- and 12-weekly intervals, resulting in süteen treatment combinations per block, Grass dry matter yield increased significantly (P < 0.05) from 7.799 to 10,993 kg ha' and from 5,715 to 14,220 kg ha' when the interval between cuts extended from 3 to 12 weeks at the first and fourth harvest years, respectively. Pasture plots cut at 3- or 6 weeks intervals exhibited much greater weed proportion than those cut at 9-, or 12-week interval. The total annual herbage dry matter yield increased significantly (P < 0.05) from 8.564 to 11,312 kg ha and from 6,814 to 10,268 in 2001 and 2004, respectively, when fertilizer N was increased from 0 to 450 kg N ha. A combination of 12-weekly interval of cut with 300 kg N ha gave a significantly higher forage grass herbage dry matter yield compared with the values got from 3- or 6-weekly interval combined with any N rate. Fertilizing at 300-450 kg N ha when combined with cutting at 9 to 12-weekly interval bet ween citts was more effective in suppressing growth and proportion of weeds.
 

Effect of cutting frequency and nitrogen application on herbage yield and nitrogen content of a degraded Panicum maximum pasture.

The effects of cutting frequency and levels of nitrogen on revitalization of a run-down pasture were investigated in 2000 and 2001 at Nsukka, Nigeria. Grass swards were cut at intervals of 3, 6, 9 and 12 weeks and received 0, 150, 300 and 450 kg N ha' nitrogen. Grass dry matter yield was increased from 52 to 75% at the 3 and 6 weeks intervals of cutting, respectively. Weed proportion was reduced from 48 to 25% with 6-weekly cuts compared with more frequent cutting at 3 weeks interval between cuts. Cutting interval did not affect the total herbage yield. The dry matter yields of leaf blade, stem and inflorescence fractions increased significantly with increase in interval between cuts in the second year. The percentage nitrogen content was highest with 3-weekly interval of cut and decreased with high interval of cuts in the second year. Crude protein yield (kg ha') was highest with 6- and followed by 3- and 9-weekly intervals of cut and decreased with lar cutting of 12-weekly interval. Fertilizer-N treatment significantly increased total annual herbage dry matter yield from 3,460 kg ha yrl where no fertilizer N was applied to 5,233 kg ha-yr' with application of 450 kg N ha-'. Grass dry matter as proportion of the total herbage dry matter was increased from 57 to 80% with the highest N rate of 450 kg Nha compared with where N was not applied, while the weed dry matter as proportion of the total herbage dry matter was reduced from 43 to 20% with the highest N rate of 450 kg N ha compared with where N was not applied at the second year. A combination of 6-weeks interval of cutting with 450 kg N ha' gave the highest dry matter yield. It was also adequate in suppressing weed. Frequent cutting at higher levels of fertilizer N (300 - 450 kg ha'') increased the nitrogen and crude protein percentages of forage foliage while 6-weekly interval of cuts when combined with higher N levels gave the highest crude protein yield per hectare per year in the foliage herbage.

Effect of feed supplementation on growth performance and plasma minerals and metabolites in hair lambs grazing Panicum maximum

Forty-eight hair lambs (12.7 ± 1.9 kg BW) that grazed Panicum maximum pasture in the daytime and were kept in yards overnight were used to evaluate the influence of a feed supplement on growth performance, plasma minerals and metabolites. Lambs were randomly assigned to two treatments: no feed supplement (control) and feed supplement (300 g/head per day). The growth performance trial lasted 77 days. At the end of the trial, blood samples were collected to determine plasma minerals and metabolites. Feed supplementation improved total BW gain, ADG and feed conversion as compared to no supplementation. Supplemented lambs had higher serum concentrations of total protein, albumin, globulin and glucose than lambs not supplemented. Packed blood cell volume, haemoglobin, urea and cholesterol, as well as blood mineral values in lambs not supplemented were similar to those of supplemented lambs. Feed supplementation of growing lambs grazing pasture in the daytime and kept in yards overnight is an important management strategy for improving growth performance and some blood metabolites related to health and nutritional status.

Effects of Nitrogen fertilisation and stocking rates on soil erosion and water infiltration in a Brazilian Cerrado farm

Ever-increasing water-food-energy demand has led to the depletion of soil resources by mainly inadequate grazing practices. Nevertheless, the effects of different grazing practices on hydrological and soil erosion processes have not yet been well-understood. Therefore, we investigated the influence of different Nitrogen application doses and stocking rates in a pasture under rotational stocking (RS) on soil erosion and water infiltration in the Brazilian Cerrado region. The experimental area was a Panicum maximum pasture and was divided into three treatments with N applications of 100, 200, and 300 kg ha-1, which respectively allowed three stocking rates from 2014 to 2018: 3 (RS-3), 4.1 (RS-4), and 5 AU ha-1 (RS-5). We respectively adopted start and stop grazing heights of 80–90 and 40–50 cm (forage height) in all treatments. To evaluate infiltration and soil erosion, we performed 28 rainfall simulations with intensities ranging from 73.5 to 93.5 mm h-1 in plots of 0.7 m2 from November 2017 to February 2018. The simulations were carried out in random sites inside the central paddocks of each treatment comprising four repetitions in each treatment under vegetation and bare soil. We found stable water infiltration (SIR) and soil loss (SLw) ranging from 65.5 to 87.2 mm h-1 and from 0.03 to 0.15 mg s-1 m-2, respectively. SIR and SLw under RS-5 were respectively 33% greater and 78% lower than under RS-3 despite the 67% higher stocking rate in RS-5. We found that higher stocking rates at optimal grazing pressure did not deteriorate water infiltration and soil erosion. Our findings reveal an opportunity for a 5-fold productivity increase while reducing soil degradation since adaptive stocking rates are supported by grazing processes along with an increase in N fertiliser dose to increase vegetation cover.

Atributos físicos e biológicos de Argissolo Vermelho-Amarelo Amazónico sob diferentes sistemas de uso e manejo

The soil quality is defined by the interaction among chemical, physical and biological attributes, which are fundamental as indicators of sustainability of the agriculture systems. Thus, the study aimed to verify the effect of the management and use systems on physical and biological properties of a Yellow-Red Argissol in the Amazon region. The study was conducted in Alta Floresta, state of Mato Grosso (Brazil) (09 o 56'20 S and 55 o 55'42 W; altitude of 285 meters). A block design was adopted, with 6 types of soil occupation and with 5 replications in plots of 100 m² each. The systems used were: natural vegetation, conilon coffee (Coffea canephora), conventional tillage (field to grow soy and maize crops), Panicum maximum (Mombaca) pasture, Brachiaria brizantha (Brizantao ou braquiarao) with liming and Brachiaria brizantha without liming. The physical attributes evaluated in this study were: macroporosity (Ma), microporosity (Mi), total porosity (Pt) and density of soil (Ds). The biological attributes were: basal respiration; microbial biomass carbon (MBC), microbial quotient and metabolic quotient (qCO2). The native vegetation system had lower microporosity and the higher rates of MBC. The qCO2 was greater in Panicum maximum pasture. Systems with pastures promoted the reduction of macroporosity and total porosity of the soil. The conventional farming systems showed lower biological quality when compared to the other systems.

Non-parasitic life cycle of the cattle tick Rhipicephalus (Boophilus) microplus in Panicum maximum pastures in northern Argentina

The aim of this work was to study the non-parasitic phase of the Rhipicephalus microplus life cycle in Panicum maximum grasses from northern Argentina, in order to provide ecological information for designing methods of tick control. Four localities were chosen as replicates. The biological parameters measured were proportion of females ovipositing, the pre-oviposition period, the proportion of egg clusters hatching, the incubation period of eggs, larval longevity, and the total non-parasitic period (time from the exposure of the female to the date of death of the last larva) (TNPP)). The following general trends were observed: I) a longer TNPP occurred when female ticks were exposed in mid- and late summer and early spring; II) the shortest TNPP occurred when female ticks were exposed from late winter to late spring; III) larvae that were active in early and mid-summer had the shortest longevity; IV) incubation periods of eggs, which originated from females exposed in late summer, early autumn and mid-spring, were longer than the incubation period of eggs produced by females exposed in late spring and early summer; V) eggs did not hatch when the engorged females were exposed in the pastures in mid- and late autumn and winter. The spelling period of the P. maximum grasses that is needed to ensure total control of R. microplus consists of 19–20weeks if the spelling starts in late spring and early summer, and 27–28weeks if the spelling begins in mid- and late summer or in autumn.

Ingestive behavior of sheep in Panicum and Brachiaria pastures in dry season

The ingestive behavior of sheep supplemented with concentrate in Brachiaria brizantha and Panicum maximum pastures were evaluated during the dry season. Twenty four male sheep of ½ Santa Ines x ½ undefined breed genotypes were used. The treatments were four feeds of cultivar grasses: B. brizantha cvs. Marandu and Piata, P. maximum cvs. Massai and Aruana. The ingestive behavior of the animals was recorded during two periods of 24 hours. The grazing time, rumination, idleness (minutes day -1 ), bite rate (bites minute -1 ), and the frequency of the animals activities in relation to defecation, urination and search for water, concentrated and mineral salt were observed. There was interaction between time of the day and evaluated cultivars based on the grazing time and bite rate response. Sheep grazing on marandu-grass showed higher grazing time between 11 am to 4 pm (257 minutes), compared to animals grazing on aruana-grass (217 minutes). The bite rate was higher for sheep on massai-grass between 11 am to 4 pm (34.32 bits minute -1 ). There was no grass effect for idleness and rumination, which can highlight the similarity of chemistry characterization and high percentage of structural components in evaluated pastures. The structural limitations and feed mass composition in the dry season caused effects on the ingestive behavior of idleness and bite rate of supplemented sheep in Brachiaria and Panicum pastures.

Performance of Nelore cattle on Panicum maximum pastures in the Brazilian Cerrado

With the increased demand for meat products, associated with environmental concerns due to global climatic and land use changes, the need to efficiently use pasture and forage resources will increase (Boval and Dixon 2012). Efforts to breed and release new forage cultivars must incorporate these concerns, ensuring that introduced material is of high quality, especially under grazing (Euclides et al. 2008). In this study, we aimed to evaluate the average daily weight gain and stocking rate of Nelore beef cattle grazing new genotypes of Panicum maximum during the rainy season in the Brazilian Cerrado.

English

A study was conducted at Nsukka, Nigeria to determine the effects of cutting height and N fertilizer application on the growth and tiller production of Panicum maximum pasture. The experiment was a 3 × 3 factorial laid out in a randomized complete block design with three replications. Treatments comprised three cutting height (5, 10 and 15 cm) and three levels of nitrogen (0, 200 and 400 kg N ha-1) resulting in nine treatment combinations per block. Plant height was significantly (P < 0.05) increased by 34 and 56% in 2008 and 2009, respectively, when cutting height increased from 5 to 15 cm. Grass tiller number per square metre varied inconsistently among the cutting heights at different harvest periods in both years. Grass height remained statistically similar among the nitrogen rates in both years but increased significantly (P < 0.05) with fertilizer N application compared with the control at some periods in both years. Grass tiller number obtained in 2008 from plots cut at 10 cm stubble height with 400 kg N ha-1 was significantly (P < 0.05) higher than those cut at 5 cm with zero N application. Cutting height × fertilizer-N interaction effect on plant height was significant (P < 0.05) in all the periods in both years.   Key words: Grass height, stubble height, tiller population, fertilizer N.

English

A study was conducted at Nsukka, Nigeria to determine the effects of cutting height and N fertilizer application on the growth and tiller production of Panicum maximum pasture. The experiment was a 3 × 3 factorial laid out in a randomized complete block design with three replications. Treatments comprised three cutting height (5, 10 and 15 cm) and three levels of nitrogen (0, 200 and 400 kg N ha-1) resulting in nine treatment combinations per block. Plant height was significantly (P < 0.05) increased by 34 and 56% in 2008 and 2009, respectively, when cutting height increased from 5 to 15 cm. Grass tiller number per square metre varied inconsistently among the cutting heights at different harvest periods in both years. Grass height remained statistically similar among the nitrogen rates in both years but increased significantly (P < 0.05) with fertilizer N application compared with the control at some periods in both years. Grass tiller number obtained in 2008 from plots cut at 10 cm stubble height with 400 kg N ha-1 was significantly (P < 0.05) higher than those cut at 5 cm with zero N application. Cutting height × fertilizer-N interaction effect on plant height was significant (P < 0.05) in all the periods in both years.   Key words: Grass height, stubble height, tiller population, fertilizer N.

The extent of plant cover and percentage dry matter of guinea grass (Panicum maximum jacq) pasture as influenced by cutting height and nitrogen fertilization

A 3 x 3 factorial experiment laid out in a randomized complete block design was conducted at Nsukka, Nigeria to determine the effects of cutting height and N fertilizer application on the extent of plant cover and percentage dry matter of Panicum maximum pasture in 2008 and 2009. Treatments comprised three cutting heights of 5, 10 and 15 cm and three levels of nitrogen of 0, 200 and 400 kg N ha‐1 resulting in nine treatment combinations replicated three times. The extent of grass cover in 2008 and 2009 was significantly (P < 0.05) increased by 62 % and 46 %, respectively, when cutting height increased from 5 to 15 cm. Bare ground area was significantly (P < 0.05) decreased by 33 % in 2008, when stubble height increased from 5 to 15 cm but was not significantly affected by cutting height in 2009. The extent of weed cover was not significantly influenced by cutting height in both years. Grass cover was significantly (P < 0.05) increased by 36 % in 2008 when nitrogen fertilizer was increased from 0 to 200 kg N ha‐1. Nitrogen application did not significantly affect the weed cover and bare ground area in both years. The dry matter content of grass was significantly (P < 0.05) decreased by 11 % and 17 % in 2008 and 2009, respectively, when fertilizer N was increased from 0 to 400 kg N ha‐1.

Adaptation of the C4 grass Panicum maximum to defoliation is related to plasticity of N uptake, mobilisation and allocation patterns

Dry mass production and persistence of Panicum maximum pastures depends on nitrogen supply. Defoliation influences N uptake and allocation patterns yet its effects on plasticity of N dynamics in P. maximum have not been investigated. Stable isotopes of N (15N) were used in order to test the hypothesis that defoliation in terms of proportion of the leaf area removed effects N mobilisation, uptake and allocation patterns in P. maximum. The plants were initially cut weekly to a height of either 0.15 m or 0.30 m for seven weeks. Eight weeks after the first defoliation, all plants were defoliated for a final time to remove 0, 25, 50, 75 or 100 % of the area of each individual leaf blade of the main tiller. Root N uptake was reduced when all leaf area was removed, but more lenient defoliation improved N uptake due to a positive effect on specific N uptake. Young leaves, side tillers and roots were the main sinks for N from root uptake. Roots of P. maximum became a net source of N for mobilisation immediately after severe defoliation. Root uptake was the main source of N for new growth in P. maximum plants. Allocation pattern of mobilised N was different from that of N derived from root uptake. It was concluded that adaptation of P. maximum to defoliation is related to plasticity of N uptake, mobilisation and allocation, but changes in N dynamics did not offset negative impacts of complete defoliation of the plants.

The quality of crop fractions of a degraded Panicum maximum pasture under different cutting intervals and nitrogen fertilizer rates

The effects of cutting frequency and levels of nitrogen application on quality of crop fractions of a degradedPanicum maximum pasture was investigated in 2001 at Nsukka, Nigeria. Cutting intervals consisted of 3, 6, 9 and 12 weeks, while N rates were 0, 150, 300 and 450 kg-N ha-1. The percentage of P in the leaf, Na in all the fractions, Fe in the leaf and stem fractions, ash in the leaf and Zn in the leaf decreased significantly (P < 0.05) with increased interval between cuts. Nitrogen application increased significantly (P < 0.05) the percentage of P in all the fractions, and the percentage of Fe, K and Zn in the leaf compared with the control. Cutting every 3 weeks produced significantly (P < 0.05) higher concentrations of iron in the leaf and stem fractions than the other cutting intervals with application of 300 kg-N ha-1. The percentage of crude fibre in the stem increased significantly (P < 0.05) from 46 to 60% when the interval between cuts was increased from 6 to 9 weeks, while there was a 6% reduction in the crude fibre content of stem when nitrogen fertilizer was increased from 150 to 300 kg ha-1. Key words: Mineral composition, cutting frequency, crude fibre, ash content, Panicum maximum, pasture, nitrogen fertilizer.

Comportement alimentaire des taurillons Girolando sur deux types de pâturages cultivés en zone subéquatoriale

Zoffoun, A. G., Babatounde,S., Houinato, M., Mensah, G. A. and Sinsin, B. 2011. Eating behavior of the Girolando cattle on two types of cultivated pastures in the subequatorial zone. Can. J. Anim. Sci. 91: 675–683. The eating behavior of the Girolando dairy cattle on the artificial grazing pastures of Panicum maximum and Panicum maximum var. C1 was studied in the subequatorial zone of Benin. Sixteen young male cattle were distributed into two groups of eight animals each. Group 1 was fed on Panicum maximum and group 2 on Panicum maximum var. C1. The animals were followed with direct observation of the different grazing activities according to the hand-plucking method.Animals fed Panicum maximum spent 66.7% of the time grazing, 9.9%in rumination, 18.1% resting, and 5.3% watering; those fed Panicum maximum var. C1 spent 54.3% of the time grazing, 12.0% in rumination, 28.4% resting and 5.3% watering. The most elevated values of voluntary ingestion were obtained on Panicum maximum pasture. On average, animals...

Comportement alimentaire des taurillons Girolando sur deux types de pâturages cultivés en zone subéquatoriale

Zoffoun, A. G., Babatounde,S., Houinato, M., Mensah, G. A. and Sinsin, B. 2011. Eating behavior of the Girolando cattle on two types of cultivated pastures in the subequatorial zone. Can. J. Anim. Sci. 91: 675-683. The eating behavior of the Girolando dairy cattle on the artificial grazing pastures of Panicum maximum and Panicum maximum var. C1 was studied in the subequatorial zone of Benin. Sixteen young male cattle were distributed into two groups of eight animals each. Group 1 was fed on Panicum maximum and group 2 on Panicum maximum var. C1. The animals were followed with direct observation of the different grazing activities according to the hand-plucking method.Animals fed Panicum maximum spent 66.7% of the time grazing, 9.9%in rumination, 18.1% resting, and 5.3% watering; those fed Panicum maximum var. C1 spent 54.3% of the time grazing, 12.0% in rumination, 28.4% resting and 5.3% watering. The most elevated values of voluntary ingestion were obtained on Panicum maximum pasture. On average, animals...

Weed community dynamics in two pastures grown after clearing Brazilian Amazonian rainforest

Mitja D &amp; Miranda IS (2010). Weed community dynamics in two pastures grown after clearing Brazilian Amazonian rainforest. Weed Research50, 163–173.SummaryTo explain the dynamics of the weed vegetation in the Amazonian pastures after clearing of the rainforest, the diversity and floristic composition of 15 Brachiaria brizantha pastures and seven Panicum maximum pastures of various ages were studied. These pastures reflect the original forest, from which they retain a high species richness (from 20 to 73 species on average per 50 m2), a high proportion of forest woody species (from 26% to 65%) and rare species (&gt;50%). The four ecological groups of plants, namely forest woody species, pioneer/secondary woody species, forest herbaceous species and secondary herbaceous species, are present in all pastures immediately after the clearing and burning of the forest and have to compete with the two sown forage species, B. brizantha and P. maximum. Because of its erect habit, P. maximum is rapidly invaded by secondary herbaceous weeds, whereas B. brizantha with its spreading habit slows down their proliferation, which therefore takes about 10 years to complete. The study showed the importance of factors such as the initial vegetation, manual‐clearing practices, duration of cropping and species grown in influencing the floristic composition of the pastures and on the diversity of weeds. These results show the response of weeds faced with human disturbance. The results also demonstrate that farmers can manage pastures in a spirit of conservation of diversity or for weed control.

Soil carbon and nitrogen in pasture soil reforested with eucalyptus and guachapele

In spite of the normally low content of organic matter found in sandy soils, it is responsible for almost the totality of cation exchange capacity (CEC), water storage and availability of plant nutrients. It is therefore important to evaluate the impact of alternative forest exploitation on the improvement of soil C and N accumulation on these soils. This study compared pure and mixed plantations of Eucalyptus grandis and Pseudosamanea guachapele, a N2-fixing leguminous tree, in relation to their effects on soil C and N stocks. The studied Planosol area had formerly been covered by Panicum maximum pasture for at least ten years without any fertilizer addition. To estimate C and N contents, the soil was sampled (at depths of 0-2.5; 2.5-5.0; 5.0-7.5; 7.5-10.0; 10.0-20.0 and 20.0-40.0 cm), in pure and mixed five-year-old tree plantations, as well as on adjacent pasture. The natural abundance 13C technique was used to estimate the contribution of the soil organic C originated from the trees in the 0-10 cm soil layer. Soil C and N stocks under mixed plantation were 23.83 and 1.74 Mg ha-1, respectively. Under guachapele, eucalyptus and pasture areas C stocks were 14.20, 17.19 and 24.24 Mg ha-1, respectively. For these same treatments, total N contents were 0.83; 0.99 and 1.71 Mg ha-1, respectively. Up to 40 % of the soil organic C in the mixed plantation was estimated to be derived from trees, while in pure eucalyptus and guachapele plantations these same estimates were only 19 and 27 %, respectively. Our results revealed the benefits of intercropped leguminous trees in eucalyptus plantations on soil C and N stocks.

Dry Matter Productivity and Forage Quality of Panicum maximum Pastures Established after Two Diferent Crop Rotation Systems

Dry Matter Productivity and Forage Quality of Panicum maximum Pastures Established after Two Diferent Crop Rotation Systems

Growth and herbage productivity of Gliricidia in Panicum maximum pasture as influenced by seedbed preparation, planting and weed control techniques

Interplanting Gliricidia (Gliricidia sepium [Jacq.] Walp.) into poor quality native grass can improve the quality of pasture. But information on methods to establish the tree legume into existing pasture is scarce. This study was designed to compare the effects of disc-ploughing, hoeing, or rotary tillage operations, and direct seeding or planting out potted seedlings on growth and dry matter yields of Gliricidia in grass pasture. The Guinea grass (Panicum maximum) pasture was first mowed to a height of 10 cm. Then the seedbed was prepared by either hoeing 0.5 m strip or rototilling 0.5 m strip with a 2-wheel tractor or disc-ploughing 1.0 m strip with a 4-wheel tractor. Eight weeks old potted seedlings were planted or seeds were sown direct. At 6 months after planting (MAP), trees in disc-ploughed strips averaged 81 cm in height, about 35% taller than trees in hoed- or rotary-tilled strips. Potted seedlings (average height 77 cm) grew 37% taller than direct-seeded trees. At 12 MAP trees in disc-ploughed strips yielded 95% more leaf DM (1170 vs. 600 kg/ha) than trees in hoed- or rotary-tilled strips. In order to intercrop Gliricidia into existing Guinea grass pasture, it is necessary to plant potted seedlings previously raised in nursery into 1.0 m wide strips disc-ploughed with 4-wheel tractor. Weed control is necessary.