Infrastructure means the basic structure of an organization or system. A company's infrastructure would include all the fixed assets, i.e., the building, equipment, machinery and tools required to manufacture their product. Although people are not fixed assets they would be included in the company's infrastructure too.
Rarely a serious problem. Look-alikes: Jumping oak gall, tubakia leaf spot, oak leaf blister, other fungal leaf spots. Jumping oak gall Brown leaves appear on trees in the white oak group in late spring. Severe infections may cause the leaves to turn black, curl up and fall. On the underside are brown galls with the larva of a small wasp inside.
Yellow leaves are typical in fall, but not in summer. Birch trees (Betula spp.) add interesting architectural form to your garden landscape. They thrive in U.S. Department of Agriculture plant hardiness zones 5 to 8, though the specific zone varies by species. Most birches produce leaves that yellow and drop in fall. If it's still summer and your birch tree leaves are turning yellow, the tree is telling you it has a problem. Most issues are easily resolved.