Geodes can be found all over the world. Areas with the most geodes, however, tend to be deserts, volcanic ash beds, or areas with plentiful limestone. In the United States, for example, you can find plenty of geodes in California, Arizona, New Mexico, Utah, Nevada, Iowa, Missouri, Illinois, Indiana, Kentucky, and Ohio.
Water and Sunlight. Basil plants are low-maintenance and do not require much care. What little care they require, however, is important to keeping the herb healthy and the foliage supple. Too much water, too little water and lack of sun will turn the basil leaf tips brown and cause them to curl. Basil -- whether growing indoors or out -- requires at least six hours of full sun to keep it healthy.
Leaf Diseases. Fungal diseases from various pathogens cause leaf spots, blotches and blisters on birch trees. Cylindrosporium and Septoria cause small spots with no borders and Colletotrichum causes larger brown spots with darker borders. Anthracnose diseases, caused by Marssonina and Discula pathogens, form angular blotches instead of round spots.