This Bur Oak was planted in our yard in 2009, probably about a 3 year old sapling at the time. This is the first year for seed production. Silvics of North American indicates that the minimum age for seed production is about 35 years. Quite a difference, and this tree has never been fertilized, just mulched. This is the first of all the oaks we’ve planted in our yard to produce, despite the fact that we have some that are much older and larger, planted as early as 2005.