Where Your Poplar Plantations and Vineyards Begin!
Rootstocks are one of the important ways grape growers can better manage for an array of vineyard problems and improve quality. Grape rootstocks can also help mitigate vineyard problems relating to soil conditions such as ph extremes, salt excess and nutrient excess. They can also improve adaptability to local climatic conditions such as shortened growing seasons, drought and excessively cool or hot growing conditions. The most important function of grape rootstocks has been to provide resistance against soil borne pest such as phylloxera and nematodes. Resistance to phylloxera and nematodes in many cases can only be provided through the use of rootstocks.
The performance of rootstocks will be very site dependent and the compatibility for a given scion/rootstock combination can vary. It is highly recommended that you consult with local vineyard manager before making your order. The best wines of the world are produced on low to moderate vigor rootstocks. It is important to adapt the rootstock choice to the soil and climate to optimize vine size. You should not use vigorous rootstocks in fertile soils, however, high vigor rootstocks can be of great value under very dry conditions, and non-irrigated vineyards.
Three North American species are the most common parents of grapevine rootstocks: Vitis rupestris, Vitis riparia,, and Vitis berlandieri.
Vitis ruprestris grows in dry, sunny sites that have periodic rain. Its plunging roots help it tap a deep water supply, but are ill suited to shallow soils in drought conditions.
Ruprestris has a very long vegetative cycle with early bud break and late fruit and wood maturation. Its growth strategy can be described as vigorous during periods of high water and nutrient availability with reduced activity during drier periods. Three of the rootstocks suited to Oregon are 3309 Coudrec, 101-14 Mgt. and Swartzmann. All are resistant to phylloxera with 3309 Coudrec and 101-14 Mgt. having moderate resistance to nematodes and Swartzmann having high resistance to nematodes.
Vitis riparia is adapted to cold climates with short seasons, the roots grow laterally and its large leaves are well adapted to shade but not drought. Bud break is early as are fruit set, although a shortened growth span would decrease the total production by the plant each year. It ensures completion of growth, fruit and wood ripening before the onset of winter. Riparia gloire is used in Oregon vineyards with deep soils and drip irrigation. Riparia gloire is highly resistant to phylloxera.
Vitis berlandieri is a vigorous climbing vine with strong fleshy plunging roots. It is the most drought tolerant and can also tolerate very low winter temperatures. It is not adapted to cool regions because of its long growing cycle and late maturity. All are resistant to phylloxera and some are more resistant to nematodes than others.
44-53 Malegue is a complex cross of V. riparia, V. cordifolia and V. rupestris . This rootstock has a deep growing root system and performs well under drought conditions. It has similar vigor to 3309 Coudrec, with moderate to early ripening. 44-53 Malegue is resistant to phylloxera and to nematodes.
For more information:
Lon J. Rombough sell grape cutting www.bunchgrapes.com
Cornell University Grape Pages www.nysases.cornwell.edu/hort/faculty/pool/grapesPagesIndex/htm