Cultivated Pastures & Fodder Production - Legumes, Sorghums, Drought-Resistant Crops, and Hay Quality

A set of vocabulary-style flashcards covering key terms and concepts from the lecture notes on lucerne, inoculation, sorghums, drought-resistant crops, and fodder conservation.

Lucerne

A deep-rooted legume fodder crop (alfalfa); considered the king of hay crops and highly valuable in SA; deep taproot (3–5 m) and used for hay and mixtures.

SA Standard

The most popular lucerne cultivar in South Africa.

Dormancy (lucerne cultivars)

Winter dormancy rating for lucerne cultivars, ranging from WD to HNWD; 1 = very strongly dormant, 10 = not dormant.

Dormancy abbreviations

WD (Winter Dormant), SWD (Semi-Winter Dormant), MWD (Moderate Winter Dormant), IWD (Intermediate Winter Dormant), NWD (Non-Winter Dormant), HNWD (Highly Non-Winter Dormant).

Rhizobium bacteria

Symbiotic bacteria that fix atmospheric nitrogen in legume root nodules, making nitrogen available to the plant.

Nodule

Root structures in legumes that house nitrogen-fixing bacteria; effective nodules are pink due to haemoglobin.

Pink nodules

Nodules that appear pink because of haemoglobin; indicate active nitrogen fixation.

Nodule bacteria specificity

Nodule bacteria are strain-specific; use the correct Rhizobium strain for a given legume.

Inoculation

Application of Rhizobium bacteria to legume seeds to promote nodulation and nitrogen fixation.

Pelleting

Coating legume seeds with adhesive, inoculum, and sometimes coating material to protect bacteria and enable fertilizer mixing.

Carboxymethylcellulose

Adhesive used in seed pelleting to attach Rhizobium bacteria to seeds (typically used as a 4% solution).

Pelleting advantages

Reduces bacteria losses during handling, protects bacteria under dry conditions, and allows mixing with fertilizers.

Molybdenum Trioxide (MoO3)

A micronutrient added during inoculation/pelleting (often 200 g) to prevent Mo deficiency in legumes.

Olsen method

Soil test method used to measure available phosphorus; lucerne requires P level higher than 10 mg/kg.

Soil pH for lucerne

Soil pH should be at least 6 for good lucerne establishment and growth.

Soil potassium (K) level

K content should be at least 120 mg K/kg soil for lucerne production.

Seed inoculation storage

Use state-approved inoculants, adhere to expiration dates, and store according to manufacturer guidance.

Seed washing (before inoculation)

Rinse seeds to remove fungicides/pesticides prior to inoculation to improve bacterial effectiveness.

Seed row spacing (dryland planting)

Plant lucerne in rows 600–1000 mm apart under dryland conditions.

Soil adaptability (lucerne)

Adapts to deep, light soils; avoid alkaline/brackish soils; shallow water table (2–6 m) is favorable; sensitive to waterlogging.

Irrigation planning factors

Consider soil type, depth, infiltration, available moisture, soil-water potential, crop factor, effective rooting depth, salt tolerance, and rainfall/temperature data.

Fodder sorghums

Annual fodder crops up to 3 m tall; three groups: Sudan grass hybrids, sorghums/Sudan hybrids, and silage sorghum hybrids.

Prussic acid poisoning

CN-containing compounds in sorghums under stress; can cause suffocation by inhibiting oxygen release from haemoglobin; graze taller than 900 mm to reduce risk.

Sugargraze

A very palatable sorghum cultivar; digestibility and sugar increase with age, suitable for forage and foggage.

Sorghum grazing management

Use rotational grazing (3–4 cycles), graze at appropriate heights, and consider green chop as an option.

Spineless cactus

A drought-resistant fodder crop with pads; highly versatile, requires different planting methods and spacing; stores water well.

Oldman saltbush

Drought-resistant fodder shrub; establishment requires care; sow Aug–Sep, transplant Feb–Mar; tolerates brackish soils.

Fodder conservation

Preserving forage as hay, haylage, or silage; moisture-based categories: high moisture (silage), medium moisture (vacuum silage), low moisture (haylage), very low moisture (hay).

Hay

Green forage cut and dried to about 10–15% moisture for storage; typically 70–80% moisture at cutting.

Quality criteria for lucerne hay

Color, leafiness, aroma; high leaf/stem ratio and lack of mould/weed content indicate better quality.

Poor hay quality indicators

Mouldiness, weeds, dust/soil, or presence of harmful chemicals; reduces palatability and safety.

TDN (Total Digestible Nutrients)

Sum of digestible fibre, protein, lipid, and carbohydrates; relates to energy available to the animal.

Leaf vs. stem in hay

Leaves are richer in nutrients; cutting at the right stage preserves leaf content and digestibility.

Drying and respiration

Respiration continues after cutting and stops around 35% moisture; excessive drying can reduce nutrient content.

Bleaching in hay

Exposure to direct sunlight can degrade carotene and vitamins; bleached hay may be poorer in quality.

Shattering of leaves

Leaves dry faster than stems; handle and rake to minimize leaf loss and preserve quality.

Grass inflorescence

Inflorescence types include panicle, spike, and raceme; harvest grasses before flowering to maximize quality.

Weeping love grass harvest timing

Typically cut when the grass is piping or at 40–50 cm growth height to maintain leafiness.

Grazing management for drought crops

Rotational grazing and careful height targets to prevent overgrazing and promote regrowth.

Carrying capacity (definition)

Maximum population size of a species that can be sustained in an environment given available resources.

Lucerne

A deep-rooted legume fodder crop (alfalfa); considered the king of hay crops and highly valuable in SA; deep taproot (3–5 m) and used for hay and mixtures.

SA Standard

The most popular lucerne cultivar in South Africa.

Dormancy (lucerne cultivars)

Winter dormancy rating for lucerne cultivars, ranging from WD to HNWD; 1 = very strongly dormant, 10 = not dormant.

Dormancy abbreviations

WD (Winter Dormant), SWD (Semi-Winter Dormant), MWD (Moderate Winter Dormant), IWD (Intermediate Winter Dormant), NWD (Non-Winter Dormant), HNWD (Highly Non-Winter Dormant).

Rhizobium bacteria

Symbiotic bacteria that fix atmospheric nitrogen in legume root nodules, making nitrogen available to the plant.

Nodule

Root structures in legumes that house nitrogen-fixing bacteria; effective nodules are pink due to haemoglobin.

Pink nodules

Nodules that appear pink because of haemoglobin; indicate active nitrogen fixation.

Nodule bacteria specificity

Nodule bacteria are strain-specific; use the correct Rhizobium strain for a given legume.

Inoculation

Application of Rhizobium bacteria to legume seeds to promote nodulation and nitrogen fixation.

Pelleting

Coating legume seeds with adhesive, inoculum, and sometimes coating material to protect bacteria and enable fertilizer mixing.

Carboxymethylcellulose

Adhesive used in seed pelleting to attach Rhizobium bacteria to seeds (typically used as a 4% solution).

Pelleting advantages

Reduces bacteria losses during handling, protects bacteria under dry conditions, and allows mixing with fertilizers.

Molybdenum Trioxide (MoO3)

A micronutrient added during inoculation/pelleting (often 200 g) to prevent Mo deficiency in legumes.

Olsen method

Soil test method used to measure available phosphorus; lucerne requires P level higher than 10 mg/kg.

Soil pH for lucerne

Soil pH should be at least 6 for good lucerne establishment and growth.

Soil potassium (K) level

K content should be at least 120 mg K/kg soil for lucerne production.

Seed inoculation storage

Use state-approved inoculants, adhere to expiration dates, and store according to manufacturer guidance.

Seed washing (before inoculation)

Rinse seeds to remove fungicides/pesticides prior to inoculation to improve bacterial effectiveness.

Seed row spacing (dryland planting)

Plant lucerne in rows 600–1000 mm apart under dryland conditions.

Soil adaptability (lucerne)

Adapts to deep, light soils; avoid alkaline/brackish soils; shallow water table (2–6 m) is favorable; sensitive to waterlogging.

Irrigation planning factors

Consider soil type, depth, infiltration, available moisture, soil-water potential, crop factor, effective rooting depth, salt tolerance, and rainfall/temperature data.

Fodder sorghums

Annual fodder crops up to 3 m tall; three groups: Sudan grass hybrids, sorghums/Sudan hybrids, and silage sorghum hybrids.

Prussic acid poisoning

CN-containing compounds in sorghums under stress; can cause suffocation by inhibiting oxygen release from haemoglobin; graze taller than 900 mm to reduce risk.

Sugargraze

A very palatable sorghum cultivar; digestibility and sugar increase with age, suitable for forage and foggage.

Sorghum grazing management

Use rotational grazing (3–4 cycles), graze at appropriate heights, and consider green chop as an option.

Spineless cactus

A drought-resistant fodder crop with pads; highly versatile, requires different planting methods and spacing; stores water well.

Oldman saltbush

Drought-resistant fodder shrub; establishment requires care; sow Aug–Sep, transplant Feb–Mar; tolerates brackish soils.

Fodder conservation

Preserving forage as hay, haylage, or silage; moisture-based categories: high moisture (silage), medium moisture (vacuum silage), low moisture (haylage), very low moisture (hay).

Hay

Green forage cut and dried to about 10–15% moisture for storage; typically 70–80% moisture at cutting.

Quality criteria for lucerne hay

Color, leafiness, aroma; high leaf/stem ratio and lack of mould/weed content indicate better quality.

Poor hay quality indicators

Mouldiness, weeds, dust/soil, or presence of harmful chemicals; reduces palatability and safety.

TDN (Total Digestible Nutrients)

Sum of digestible fibre, protein, lipid, and carbohydrates; relates to energy available to the animal.

Leaf vs. stem in hay

Leaves are richer in nutrients; cutting at the right stage preserves leaf content and digestibility.

Drying and respiration

Respiration continues after cutting and stops around 35% moisture; excessive drying can reduce nutrient content.

Bleaching in hay

Exposure to direct sunlight can degrade carotene and vitamins; bleached hay may be poorer in quality.

Shattering of leaves

Leaves dry faster than stems; handle and rake to minimize leaf loss and preserve quality.

Grass inflorescence

Inflorescence types include panicle, spike, and raceme; harvest grasses before flowering to maximize quality.