Pond Boss Forums AQUATIC VEGETATION Identifying plants Illinois Pondweed?

A little more about 'cabbage' as described from the link above BrainerdGuide; Northern Tips- Early Summer:
""Cabbage weeds are an important structural element for northern fishing in the Brainerd Lakes area. If there�s a good stand of cabbage weeds present on a lake, it�s a sure bet that there�s a few northern pike close by. A cabbage weed is easily identified by its long slender stalk and broad, flat leaves. The color of healthy cabbage is vivid green. The leaves are spaced every 14 to 16 inches and attached on alternating sides of the plant's stalk. These leaves are very fragile. They tear almost like lettuce, hence the name cabbage. But the stalk is tough. The cabbage weed can reach lengths of sixteen feet in the clean waters of the Brainerd Lakes area. The shape and location of a lake�s cabbage beds can change yearly. Exposure to sunlight has a great deal to do with the plants location. The cabbage plant is very light sensitive. On years when the water levels are down, the extra sunlight entering the water will cause the shallow edges of the cabbage bed to burn. On years when the water levels are up, the reduced sunlight will cause the deeper edges of the cabbage bed to wither. In some extreme cases, the entire cabbage bed may disappear on a given year. Early each summer, I try and take advantage of the first few calm days to learn the new shapes of the cabbage beds. The top of each cabbage weed contains a small seed pod. It�s slender and only 2 to 3 inches long. This is the only part of the entire cabbage plant that sticks out of the water. A good cabbage bed looks like a bunch of little pencils sticking out of the water, one every 2 to 3 feet, on a calm day.""

It sounds to me as this 'cabbage' is some species of broadleaf pond weed (Potamogeton), very likely bigleaf pond weed or similar. Leaf spacing of 14"-16" is probably for plants growing in deeper water (8'-12'deep) where stalks have to 'stretch' for light in deeper water. Shallower growing plants (2'-5') normally will have leaves much closer together and similar to the pictures posted above. Note in clear water it can grow to 16ft deep; deeper depths than many ponds. Of those that I've seen, the stands of weed beds have lots of open spaces for fish to hide and hunt through, thus the good pike fishing during early summer mentioned in the guide series.

Maybe essshup can get some more pictures of the plant in a few weeks when seeds and maybe floating leaves are present.