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Types of cuttings • Stem cuttings – Hardwood • Deciduous • Narrow-leaved evergreen – Semi-hardwood – Softwood – Herbaceous • Leaf cuttings • Leaf-bud cuttings (single-eye or single-node) • Root cuttings Hardwood deciduous stem cuttings • Definition: segments of shoots from matured, dormant hardwood stems after leaves have abscised; before new shoots emerge in spring • Features: easy to prepare, not readily perishable, require little or no special equipment • Many deciduous crops are propagated this way: – Ornamental shrubs - e.g., privet, forsythia, rose rootstocks – Fruit spp. - fig, quince, mulberry, grape – A few trees: willows, poplar Methods of preparing/handling hardwood deciduous cuttings before planting • Direct spring planting – Stems gathered, stored cold till spring – Cuttings made at planting time • Direct fall planting – Cuttings planted directly into the nursery in the fall – From So. Canada (orn. shrubs) to Texas (rose rootstocks) • Warm-temp pretreatment – Cuttings taken in the fall (dormant period) – Cuttings treated with rooting hormone (PGR), stored warm 35 weeks, placed back in cold till spring Hardwood evergreen (narrow-leaved) stem cuttings • Definition: dormant (late fall to late winter) cuttings with functioning leaves • Features: cuttings are slower to root than those of deciduous spp; moisture loss must be prevented; poly or light mist , rooting hormone (PGR) treatments enhance rooting • Arbor-vitae (Thuja), low-growing junipers (Juniperus) root easily, yews (Taxus) fairly well Semihardwood stem cuttings • Definition: cuttings from woody, broad-leaved evergreen species and leafy summer and early fall cuttings of deciduous plants with partially matured wood • Features: rooting under high humidity is essential to prevent leaf abscision • Ornamental shrubs (camellia, pittosporum, rhododendron, euonymous, evergreen azaleas, holly, and fruit spp. (citrus, olive) Softwood stem cuttings • Definition: cuttings from soft, succulent new spring growth through early to mid-summer (before green wood begins to mature) • Features: high humidity during rooting; very useful for difficult-to-root spp. • Many ornamental woody shrubs (lilacs, weigela, spiraea) Herbaceous stem cuttings • Definition: cuttings from succulent nonwoody plants such as mums, coleus, carnations, foliage spp.) that retain a portion of the stem and (typically) leaves and a shoot tip • Features: humidity control is usu. required; rooting occurs quickly and in high percentages for most spp.; v. useful for many greenhouse floral crops Herbaceous leaf cuttings • Definition: cuttings made up of a leaf blade, or a leaf blade and petiole • Types cuttings: – Spp. with primary meristems (plantlets arise from notches around the leaf margins) such as Bryophyllum – Spp. with secondary meristems (adventitious buds, shoots, and roots form at the base of the leaf and develop into the new plant) such as African violet (Saintpaulia) Leaf-bud cuttings (single-eye or single-node) • Definition: a cutting consisting of a leaf blade, petiole, and a short piece of stem with attached axillary bud • Features: usually used where material is limited, and when adventitious shoots will not form from leaf cuttings; humidity control is necessary • Useful for many greenhouse floral crops Root cuttings • Definition: cuttings taken from roots • Features: – Usu. cuttings are taken in late winter or early spring – Correct polarity is important – A shoot and root system are formed adventitiously (not all spp. are competent) – Some forms (thornless cultivars, variegated forms) can’t be propagated this way