Carrizo Citrange Trifoliate Hybrid Citrus Rootstock Seedling

Carrizo is hybrid of Citrus sinensis (Washington Navel orange) and Poncirus trifoliata, originating from a cross
made at Riverside California in 1909, within the USDA citrus breeding program. Carrizo is
often considered identical with Troyer, although separate clones are maintained in many
locations. Characteristics of Carrizo and Troyer are very similar. With most scions, Carrizo provides excellent early bearing of young trees, internal fruit quality is excellent, and fruit size is usually medium to large. Carrizo is vigorous, and develops medium to large tree size (depending on the scion cultivar), or what is often considered “standard” tree size. Carrizo is sensitive to alkaline-induced chlorosis and in some cases trees have severely declined as a result of iron and other trace element deficiencies
on saline, calcareous and especially high pH soils. Another major disadvantage of this rootstock in some areas is the tendency to induce a higher incidence of creasing. Carrizo induces higher acid levels than rough lemon, but while this has occasionally created problems with Valencia, Minneola tangelo, and grapefruit in the cooler production areas, it is advantageous in hot areas. In the absence of limiting disease problems or soil conditions, Carrizo is an excellent rootstock for sweet orange, grapefruit, and most mandarin hybrids. The main advantages of Carrizo citrange are intermediate resistance to Phytophthora root rot, nematode and CTV tolerance, good internal quality, earlier external color compared to Swingle citrumelo, and medium tree size. Carrizo is not compatible with Eureka and other Eureka-type lemon selections.

• Dwarfing Capability: Produces large, vigorous, and upright trees.
• Yield: Reliable performance in commercial orchards.
• Cold Hardiness: Moderate cold tolerance.
• Appearance: Trifoliate, although young vigorous shoots might sometimes show unifoliolate or bifoliolate leaves, thorny.
• Grafting: Nearly indistinguishable from Troyer.  Generally faster growing in the nursery than Poncirus trifoliata, with earlier external fruit coloring compared to Swingle.
• Soil Preference: Performs best in well drained, sandy soils; unsuitable for heavy clay, high salinity, or high pH (calcareous) soils.
• Disease Resistance: Excellent resistance to Citrus Tristeza Virus (CTV) and good tolerance to Phytophthora root rot.

Grown as a 12" to 24" single trunk whip with little or no branching. Calliper measures 1/8" to 1/4" diameter. Additional growing time may be required to reach sufficient calliper for your preferred method of grafting.