Crop Classification

Thomas G Chastain

CROP 200 Crop Ecology and Morphology

• Based on:

1. Morphology – flower parts, vegetative characteristics, seeds, etc.

2. Genetics – chromosome number, etc.

3. Chemical nature (chemotaxonomy) –classification of plants based on chemicals found in plant parts, seeds, etc.

Crop Classification - Botanical System

Crimson clover

inflorescence

(left) onion

inflorescence

(right) TG

Chastain photos.

Crop Classification - Botanical System

• The botanical system is a binomial system; two names are used to describe the plant and is otherwise known as the scientific name.

• The scientific name is composed of the genus and the specific epithet (or species):

Solanum tuberosum

Genus Specific epithet

Potato tuber (top), potato flower and

foliage (bottom) TG Chastain photos.

Crop Classification - Botanical System

Chewings fescue flowers (TG

Chastain photo)

Kingdom: Plantae (plants)

Division: Magnoliophyta (flowering plants)

Class: Liliopsida (monocots)

Order: Cyperales (grass-like families)

Family: Poaceae (grass family)

Genus: Festuca (fescue)

Species: rubra (red fescue)

Subspecies: fallax (Chewings fescue)

Variety: refer to botanical varieties, not cultivated varieties or cultivars

Ecotype: a local variant

The scientific name for Chewings fescue is Festuca rubra ssp. fallax.

Crop Classification - Important Crop Families

• Poaceae – grass family - Small grain cereals (wheat, barley, oats), corn, rice, sugar cane, forage and turf grasses.

• Fabaceae - legume family – Grain legumes (peas, beans, lentils, chickpeas, lupin), forage legumes (alfalfa, clover), soybean.

• Apiaceae – carrot family – carrot, celery.

• Asteraceae – sunflower family – sunflower, lettuce.

• Solanaceae – tomato family – tomato, potato, pepper.

• Brassicaceae – mustard family – cabbage, canola, mustard, camelina, kale, broccoli, cauliflower.

• Cucurbitaceae – cucurbit family – squash, pumpkin, cucumber, watermelon.

• Chenopodiaceae – goosefoot family – sugar beet, garden beet, quinoa.

• Malvaceae – mallow family - cotton.

• Lamiaceae – mint family – mint, numerous herbs.

Crop Classification - Use Characteristics

• Crops can also be classified according to their use characteristics.

• Cover Crop – grown to protect soil from erosion.

• Green Manure Crop – a crop grown to be incorporated into the soil so as to provide fertilizer nutrients and organic matter.

Crimson clover (TG Chastain photo)

Crop Classification - Use Characteristics

• Sugar Crops – Sugar cane, sugar beet.

• Beverage Crops – used in production of beverages (hops, malting barley).

• Fiber Crops – harvested for fibers used for clothing, industrial applications, etc. (cotton, flax).

Barley field (above), flax stems (top), flax stem

broken to show fibers within (bottom), TG

Chastain photos

Crop Classification - Use Characteristics

• Forages – Animals use the vegetative parts of these crops for food. Types of forage crops include:

• Pasture crops – used directly in grazing. (tall fescue)

• Hay crops – are cut and dried in the field, baled, and stored for later use. (alfalfa)

• Silage crops – are cut, but not dried, and are then fermented under anaerobic conditions. (corn)

Alfalfa in flower (top), clover foliage (bottom)

TG Chastain photos

Crop Classification - Use Characteristics

• Grain Crops – These are annual crops, mainly members of the grass family and are grown for the edible seed. Grown for human or animal consumption.

• Includes the small grain cereals such as wheat, barley, and oats. Other grain crops include rice, corn, and sorghum.

Rice (top left), sorghum (bottom left)

Crop Classification - Use Characteristics

• Pulse Crops (also known as grain legumes) – Large-seeded legumes which are harvested for the edible seed or oil in edible seed.

• Contain higher seed protein content in seeds than the cereal grain crops. (soybean, peanut, peas, beans, chickpea, cowpea, lentil).

Soybean (top), chickpea (bottom)

Crop Classification - Use Characteristics

• Oil Seed Crops – harvest seeds containing edible and industrial oils (soybean, sunflower, safflower, rapeseed, canola, flax, camelina, mustard, and meadowfoam).

Safflower (top left), canola (bottom

left), meadowfoam (above) TG

Chastain photos

Crop Classification - Use Characteristics

• Root and Tuber Crops – harvested for under ground storage organs. Root crops include sugarbeet, radish, carrot, and cassava. Potatoes are harvested for the tubers while onion and leek are harvested for the bulb.

Carrot (top), sugarbeet field (right)

Crop Classification - Use Characteristics

• Energy Crops – harvested for energy production – includes oil seed crops for biodiesel, corn and others for bioethanol, and biomass crops.

Corn (left), sunflower (above) TG

Chastain photos

Crop Classification - Plant habit

• Crops can be classified on the basis of their habit.

• Annuals – complete life cycle in one year and the species in perpetuated by seeds. Winter annuals: seed germinate in fall and plants mature during the following summer (winter wheat). Spring annuals: seed germinate in spring and the plant matures in summer (spring wheat, corn, soybeans).

• Perennials – continue development for more than 2 years. (alfalfa, tall fescue).

Tall fescue (TG

Chastain photo)

Crop Classification - Plant habit

• Biennials – need 2 growing seasons to complete life cycle:

• Year 1 – vegetative development usually in the form of a rosette

• Year 2 – reproductive development, flower stalks form in a process known as bolting. (carrot, sugar beet, onion, cabbage). Year 1 - Rosette Year 2 - Bolting

(TG Chastain graphics and photos)

Crop Classification - Plant habit

• Determinate Crops – Flowering is confined to a specific period of time in these crops, at the end of vegetative growth.

• Indeterminate Crops –Flowering is continuous and not confined to a specific period in these crops, as flowering overlaps with vegetative growth.

Indeterminate tomato cultivar

(TG Chastain photo)