Trees looking yellow or suffering from poor leaf growth? One application of Nutriboosters directly into treesactive-layer cambial zone can relieve symptoms of iron chlorosis and manganese, phosphorus, and potash deficiencies with visible results in as little as 5 days. Wedgle Direct-Inject Tree Treatment System works without drilling or wounding trees. Most applications take 5 minutes or less. Injectable nutrients are safe to use year after year.