If the leaves of a Ginkgo tree sprouted and then turned brown and died, there could be several potential causes for this issue. Here are a few possible explanations:

1. Frost Damage: Ginkgo trees are generally hardy, but new leaves can be susceptible to frost damage. If the tree experienced a late frost or a sudden drop in temperature after the leaves emerged, it could cause the leaves to turn brown and die.
2. Drought Stress: Ginkgo trees prefer well-drained soil but also require regular watering, especially during dry periods. Insufficient watering or prolonged drought can stress the tree and result in browning and shedding of leaves.
3. Disease or Pest Infestation: Ginkgo trees are generally resistant to diseases and pests, but they can still be affected. Diseases like anthracnose or bacterial leaf spot and pests such as aphids or mites can cause leaf discoloration and defoliation.
4. Nutrient Deficiency: A lack of essential nutrients, such as nitrogen, iron, or manganese, can lead to leaf yellowing, browning, and premature leaf drop. Soil testing can help determine if nutrient deficiencies are the cause.  Here is a link https://soiltest.cfans.umn.edu/testing-services/lawn-garden

It's essential to examine the affected leaves and the overall health of the tree to better understand the cause of the browning and dying leaves. If the issue persists or worsens, it may be beneficial to consult with a local arborist or horticulturist who can assess the tree and provide specific guidance based on the conditions in your area.