AGRI 31 Crop Science Lab Exercise: Crop Identification and Classification

Identification of Crops

• Crops are diverse, and identification is essential in agriculture, particularly in propagation, collection, weed, and toxic plant discrimination.
• Identification is made by comparing morphological characteristics of an unknown plant to a known one.
• Common names are not universal and may differ from one location to another, hence scientific names are used to formally identify crops.

Classification of Crops

• Crops can be classified according to their life cycle, mode of reproduction, growth habit, and agronomic or horticultural classification.
• Life cycle in cultivation may differ from biological life cycle.

Growth Habit

• Herbs: succulent plants with self-supporting stems.
• Vines: succulent plants without self-supporting stems.
• Shrubs: may have several main branches with no trunk and rarely grows higher than five meters.
• Trees: with single central stem to which branches are attached, usually taller than a shrub.
• Liana: long-stemmed, woody vines that are rooted in the soil and use trees and other structures for vertical support.

Classification of Crops based on Use or Purpose

• Cereals/grain crops: grasses grown for their grains (e.g., rice, corn, wheat, sorghum).
• Green manure: a crop that is plowed under while still green and growing to improve the soil.
• Cover crop: a crop grown to provide soil cover, prevent soil erosion by wind or water, improve soil, and control weeds.
• Companion crop: a crop sown with another crop and harvested separately.
• Trap crop: a crop that attracts pests away from the main crop.
• Catch crop: a short-seasoned crop grown immediately after the failure of the main crop to utilize residual resources.
• Soilage: grasses grown, cut, and directly fed to animals.
• Silage: grasses grown, cut, fermented, and preserved before being fed to animals.