Are turkish hazelnuts edible?
First off all let me say something about this tree.



Turkish hazelnut (Corylus colurna) is a slow growing pyramidal tree approximately around 25 m (82ft) tall, with a stout trunk up to 1.5 m (4 ft 11 in) in diameter. Leaves are deciduous, rounded, 6-15 cm long and 5-13 cm across, softly hairy on both surfaces. Corylus colurna is actually the largest species of hazel. The name Korylos (korys) comes from Greek and means helmet. The tree is dioecious.



Nuts are about 1-2 cm long, surrounded by a thick, softly spiny and bristly involucre (husk) 3cm diameter. The nuts are born in cluster of 3-8 together. The nuts mature in September and are edible, with a taste similar to common hazel (Corylus avellana). The nuts have a very hard shell, approximately 3 mm thick, which it makes them a little hard to open. Nut production is very irregular and occurs every two to three years. 



Source

https://en.wikipedia.org/wiki/Corylus_colurna
http://www.missouribotanicalgarden.org/PlantFinder/PlantFinderDetails.aspx?taxonid=277856
https://www.chicagobotanic.org/plantinfo/tree_alternatives/turkish_hazelnut