Dormancy through Bud-Swell

The dormant bud in the image at left is covered by many layers of bud scales. Bud scales are tough modified leaves that serve as protection for the developing bud. Notice that this bud has whitish, hairy trichomes located at its center.
Dormant Bud on Cabernet
A longitudinal section of a dormant bud shows the apical meristems (red arrows), and leaf primordia (yellow arrows). Many dormant buds contain up to three buds with their respective apical meristems and leaf primordia. The bud in the image contains two. The large bud on the left is termed the primary bud. If it is damaged during budbreak, the secondary bud will grow in its place. However, the secondary bud will not produce as much fruit as the primary bud would have.
Dormant Bud LS
This image of a dormant bud shows the apical meristem (red bracket), very recently developed leaf primordium (blue arrow), and several older leaf primordia and bud scales (yellow arrow).

Dormant Bud LS

A dormant bud nearing bud-break will begin to enlarge. This is appropriately termed bud-swell. The inner bud is enlarging and will soon break free from its protective bud scales.
Bud-swell on Cabernet

Bud-break though Early Shoot Growth

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