Colossal grafted chestnut tree is a tree produced from a chestnut harvested from a Colossal chestnut tree, sprouted, and then when the seedling is of proper size is grafted with wood from the mother tree. The Colossal chestnut tree is the top producing commercial chestnut tree, producing heavy loads of very large chestnuts mostly falling free from the burr starting at the age of 2-3 years. Full production in 12 - 15 years depending on the location. Not a pollen producer, it needs a pollinator.
The Colossal chestnut tree is a European x Japanese hybrid cultivar producing medium sized chestnut trees with heights reaching about 60 feet and 25-35 feet wide. The tree can be kept pruned to the size that fits your location. Winter cold/freeze damage can occur when winter temps drop below -20 F. Chestnut blight resistance is minimal. To produce nuts you will need at least 2 trees with one of them producing pollen (pollinators: Marival, Prococe Migoule, Basalta #3, Marigoule, Marsol, Yooma, and Okie). (Availability - Dec 2017).
Pedigree: sativa * crenata
Chestnut blight susceptible: Yes
Bloom time: Early
Median female flowers: 5
Maximum female flowers: 7
Tree growth habit: fast growing with medium height
Nut per lb: 12 - 24 depending on growing season and water availability
Nuts per burr: Usually 3
Production: California central valley 4500 lbs per acre - other places it produces about 2000 lbs per acre
Pellicle: removal varies depending on growing conditions
Split kernels: Some
Cold Hardy: -20F