Forage Crops

HCS412 Forage Crops
Sustainability &Biodiversity

Introduction	A biodiverse landscape (crop land, grazing land, indigenous forest, exotic forest/lumber, rural infastructure and a National Park) - but is this sustainable??
What is sustainability?
In what ways are forages more sustainable?
In what ways are forages less sustainable?
Biodiversity
Farm Management

	Whether or not we feel "green" or adopt "ecological" practices, agriculture is a biological system and is constrained by the laws of biology - "you can't beat nature"
	The world population and food demands are unprecedented
	Historical evidence is that cultures which have not protected their soil have died out
	With increasing population in Ohio, there is an increasing interface between urban and rural communities, which is becoming increasingly intolerant of off-farm emmisions
	CFAES has adopted the "ecological paradigm" (production efficiency, economic, social, environment)

What is sustainability? (pg 290 & 335)

	keeping agriculture viable for a long period of time
	maintain organic matter and soil organisms
	balance between nature and humans
	a system where inputs = outputs, without interuption of other systems
	stabilizing the natural environment, by use of natural methods e.g. no till, precision ag systems
	producing what is needed to survive, food population balance

More on what is sustainability?

	Many definitions – none is universally accepted
	The term implies: Continued ecosystem services (production, clean water, clean air)
	physical/biological viability - protected resources (soil, water, plant, animal, biodiversity) economic viability (farm income/profit, rural infastructure) social viability (lifestyle, community, consideration of future generations)
	What is being sustained? (farm production, farms, animal production)
	How long should sustained mean? (1 generation, 100 years, 1000 years) – science can’t agree on the significance of CO2 effects after 100 years of change
	Technology mask – is use of technology masking a declining production potential (e.g. from soil loss?, how would this be measured?)
	Sustainability is a sociological concept – it is totally in terms of human impacts and consequences.

	protect the soil compared to cropping
	generally more favorable to wildlife
	grazing with livestock is favorable to better nutrient cycling
	increased OM compared to grain
	"permanent"
	more diverse - suits a greater variety of production systems, and greater variability in the environment (soil/climate)
	cheaper

More on ways are forages more sustainable?

	Nitrogen fixing legumes
	Less dependant on labor inputs
	Soil stability, less soil disturbance
	Builds organic matter
	Habitat for wild animals
	Ease of biological control
	Less use of fossil fuels
	Year-round feed source
	Less herbicides and insecticides
	Thousands of years of grasslands & grazing
	Suited to precision agriculture
	Less CO2 produced

	Soil damage from animal treading when the soil is wet (pugging/puddling), compaction
	Resistance to herbicides, antibiotics and de-wormers
	Lower farm returns?
	Declining consumption of red meats, lower prices
	Preference for grain-fed over grass-fed

	Defined as “the variety of life-forms that exist in a particular place” Plant, microbiological, and animal components Biodiversity is one component of sustainability Sub-species effects – genetic diversity
	advantages first proposed by Charles Darwin in 1856 (greater production, more even production, greater stability)
	2 components, species richness (species number) and distribution Even vs uneven composition (role of dominant and rare species)
	Range condition can be scored by a system comparing current species composition with the desired composition. Introduced species = impaired condition. The argument for native species is based on the hypothesis that years of natural selection (pre-settlement) have resulted in the species composition best suited to that environment
	Rio accord (1992) – if each country protects its own biodiversity the world’s biodiversity will be protected Hence there is an emphasis on indigenous (native) biodiversity In some areas restoration and preservation of federally owned land is only with native species (pg 328 & 335)

Practical aspects

1) Benefits of mixtures (especially grasses and legumes orcghardgrass alfalfa, ryegrass-white clover)

2) Dilution of undesirable effects – e.g. bloat if legumes exceed 30% of forage, dilution of endophyte in tall fescue and ryegrass

3) Complimentary growth patterns e.g. C3 & C4 species, C3 species and legumes, orchardgrass

4) Faster recovery from drought

5) Use of native species for full or partial restoration (some question about using seed having the appropriate genetic diversity)

6) Exploit spatial variability (e.g. vary species composition on sun-facing and shade-facing slopes)

7) Genetic variation – the basis of plant breeding; Many differences between cultivars and varieties

8) Some lines sold are blends of varieties e.g BG34 (Barenbrug ryegrass) is a blend of 4 different varieties