A veteran resident and historian of this area told me about this tree. It stands on the grounds of the original Edmond High School, built in 1924.
The tree is located at the NW corner of N. Boulevard and Campbell. An issue of the Edmond Sun newspaper from 1906 describes the planting of this tree, when the property was the location of the original Mitch Park. The Oklahoma State Forestry Service checks the health of this tree annually.
The tree is a Bois d'arc (also known as Osage Orange, maclura, hedge-apple or "horse apple'). It's a member of the fig-mulberry family (Moraceae) and is native to Texas and Oklahoma. This is a female tree and does produce the light green fruit.
The trees were used by Indians to make bows. In the 19th Century, "hedge-apple" was planted by farmers and kept pruned to form a spiny headgerow fenceline. When real barbed wire was invented, this tradition was discontinued. Female trees have little pistillate flowers in little radial buttonballs, which grow into greenish apple-sized fruits. The heavy fruits fall suddenly within a day or so, in the autumns. The sap is full of latex, and the sap and fruit juice is somewhat distasteful, at least to humans.
The tree is within 20 ft. of two main roads in town, and parking spots are within 10 ft. of the tree on Campbell Street. The tree is estimated to be 35 ft. high. Its girth at 4.5 ft. from ground is 12+ ft. The girth one foot above ground is 15.8 ft.
UPDATE: 10/26/2020 - Edmond experienced a severe ice storm today and trees throughout the town have been heavily damaged. Sad to say, this beautiful 114 year old tree lost a large branch in the melee. But it is strong and resilient and we expect it to carry on. Will take another photo in late Spring of 2021 to see how it fared.