Q.leaves turning yellow and brown
The leaves on my hazelnut trees and my grape vine are turning yellow and brown. The growth is much less vigorous. My honeysuckle also seems to be less vigorous. Can I save them? The honeysuckle and grape vine are 5 years old and the hazel is only one year old.

Since both planting are showing signs of the same browning leaves it would indicate an insect or fungus issue.
Examine the leaves and plants carefully to see if you can identify any pests or signs of fungal disease.
You can treat with Neem OIl as is does work as both an insecticide and fungicide.
https://www.gardeningknowhow.com/ornamental/vines/honeysuckle/honeysuckle-vine-care.htm
https://www.gardeningknowhow.com/edible/fruits/grapes/treating-grapevine-problems.htm
https://www.gardeningknowhow.com/plant-problems/pests/pesticides/neem-oil-uses.htm