can i use walnut tree leaves as a compost?

Walnut trees do produce a toxin called juglone that can kill or retard the growth of other plants. However, in a well maintained and balanced compost the juglone in walnut leaves will break down in five to six weeks. The finished compost can be used on your plants without worry.

As noted in the link below a chemical (juglone) found in black walnut leaves does interfere with growth in many other plants, especially those of the nightshade family (potato, tomato, etc). I have also heard that pecan leaves (which are in the Walnut family) do the same thing, but I don't have any evidence to support that claim.

Juglone is found in much higher concentration in the roots, buds and nut hulls. Walnut roots can extend 50 to 60 feet from the trunk of the tree, and so can affect susceptible plants that are not under the leaf canopy. The link below also notes which plants are tolerant of juglone. Tolerant meaning resistant not immune.

Yes you are indeed correct, my dear!

u are correct