I agree with Tom that leaf arrangement and morphology is good information to include in PlantFiles. Things as simple as Opposite vs. Alternate arrangement of foliage make all the difference in being in the right hemisphere when trying to ID an unknown. This isn't the worst chart in the world, but I would not suggest that DG include information that isn't correct.
I can point out where there are problems with this particular chart, but it would be really difficult with typing to demonstrate a better rendition.
The chart should not list alternate and opposite under SHAPE. These terms refer to arrangement of leaves along a branch, NOT to shape of the leaf.
That chart uses the term stem throughout. Unfortunately, the chart uses stem to refer (properly) to the branch in some cases (see the image of perfoliate) - and sometimes not. The stem on a plant is NOT part of the leaf.
I expect that the petiole is the part referred to most often when the chart uses the term stem. See images of cordate, obcordate, and peltate under SHAPE.
So, that will confuse users of this chart when looking further for information or when trying to apply this information elsewhere.
I would refer DGers to Michael Dirr's text The Manual of Woody Plants in the very front, for a good read on plant part terms. It is presently in a logical methodical fashion, and there is a glossary of terms in the back to get even further descriptions.
The image copyright holder is allowing it to be copied, distributed, modified and adapted as long as credit is given to the original author. This could easily be made into a chart that works for the Plant Identification forum. I would be happy to do the graphic work if I had a couple of experts guiding me. I'm sure we could come up with something that could be used as a sticky, providing the admins at DG give their stamp of approval.
ViburnumValley, I believe your second response is much more appropriate for the post in explaining why you think the way you do. So in all reality, the chart is not too off and it would be applicable for beginners to have such a chart to help us along. I don’t find the mistakes you have pointed out to be too obnoxious and as HelloMissMary pointed out, the reason why I picked this chart was due to copyright. I do believe that a chart of this sort would be very helpful for many, like me, who have a serious desire to learn. The first response could put off a beginning gardener and even squelched the desire to learn. It could be found intimidating and run off beginners. I am simply not willing to give up so easily simply for the fact that someone who has been doing it longer than I have, said “NOT.” We all were beginners at one time, right? So then, the chart or something similar could be acceptable in aiding gardeners to come closer to accurate answers while trying to identify weeds and plants of various zones until something slightly more categorized came along. Putting my ignorance aside, I had no idea that such a study of leaf morphology existed. I was very excited to have another chapter of knowledge open up. I am certain that there are others who would enjoy the knowledge as well. Blessings to you.