Handbook of Plant and Crop Physiology

96 CHONG ET AL.

TABLE 3

Continued

Pretreatment

Stratification (months)

Plant

Collection

Warm

Cold

Species

type

date

Storage

Scarification

(20–30

C)

(1–5

C)

Remarks

Chionanthus virginicus

FringetreeOleaceae

Cladrastis lutea

YellowwoodFabaceae

Cornus alternifoliaC. canadensisC. floridaC. kousaC. masC. racemosaC. sericea

DogwoodCornaceae

Cotoneaster apiculataC. horizontalis

CotoneasterRosacease

Crataegus arnoldianaC. crus-galliC. mollisC. phaenopyrum

HawthornRosaceae

DT or DS

DT DTDSDTDTDSDSDS BESBES DTDTDTDT

Oct. Oct.–Dec. Aug.–Sept.Aug.–Sept.Oct.Sept.–Oct.June–JulyAug.–Sept.Aug.–Sept.Oct.Oct. Oct.–winterOct.–winterOct.–winterOct.–winter

1–2 years at

0–5°C

3 years at 1–5°C 2 years dry at

5°C

3 years at 5°C3 years at 5°C3 years at 5°C3 years at 5°C

H

SO 2

4

for 30 min

before orinstead of coldtreatment

H

SO 2

4

2 hr

H

SO 2

4

2 hr

4–5 hr H

SO 2

4

2–3 hr H

SO 2

4

1–3 2–5^3 4–5^3

2–3^3 2–3^33 3–4^3 3–4^33 3–4^6333

Collect seeds when fruits

turn purple. Fall sowingwill produce seedlings thesecond spring.

See note 5. Collect fruits as soon as

ripened to avoid birdremoval. Fleshy coveringsmay enhance dormancyand should be removed.

See note 5.Warm stratification for 5–6

months before coldtreatment may be usedinstead of acidscarification. Acid-treatedseeds may be sownoutdoors in fall.

Macerate fruits in water to

remove pulp from seeds.Freshly harvested seedsmay need lesspretreatment time. Seedcoat may becomeimpermeable after drying.

See notes 4, 5, and 6.