A tulip tree (Liriodendron tulipifera) is a fast-growing tree that requires well-draining soil. Fortunately, it can withstand soggy soil conditions every once in a while, such as after a spring thaw or hard rain. However, if your soil is too wet too often, you will notice that your tree looks as if it is not watered enough. Since you know it is, the withered and dropped leaves could be a sign of overwatering. The good news is that if you catch the problem early, you have a chance of stopping the damage--the most severe being irreversible root rot--and returning the tree back to full health.
Stop watering your tree. During the growing season (spring until fall), a tulip tree only needs about an inch of water a week in order to thrive. If rainfall meets this need, you don't need to water it that week. During the winter, rain and snow usually meet the water needs of a tulip tree; therefore, do not water your tree during the winter.
Level out the water ring, also known as a water well, if applicable. When you planted your tulip tree, you may have formed a small mound around your tree to help direct the water to the outer edges of the tree. Go ahead and level that ring out if your tree is receiving too much water.
Remove the mulch. Mulch helps retain moisture. So by removing it, the soil will dry out more quickly. Once your tree is well again and you are on a good watering schedule, you can always replace it.
Transplant your tree if it's planted in poor soil that doesn't drain well or is consistently soggy, such as near a pond. The younger the tree, the easier this will be and the more likely your tulip tree will survive. When you dig, be sure to get as much of the root ball as possible and then transplant it to an area that is in full or partial sun (full sun is best) and is in soil that drains well. Adding equal amounts of course sand and compost to the planting site will improve drainage. If you see rotting or decaying roots, cut them off. They will only continue to rot and damage more of the roots.