Many substrates near pond and streams ,or within humid forest will harbor flourishing colonies of algae. greenish soils may be picked up on a piece of tin and transferred into bottle lid. The bottle is then screwed into the lid and kelp in the inverted position while it is transported back to laboratory. Remove bits of bark containing green algae with a pocket knife. Areas such as water seeps along road banks ,bird baths,fish pond,and the like may also provide source of less common species of algae.