I would like to add these sources to the author’s :
Vitamin D – the article is missing a crucial and easy to set up source– fresh shiitake mushrooms. “A fresh shiitake boasts about 100 IU of vitamin D per gram, but if you dry it in the sun, it creates 10,000 IU. If you dry it upside down in the sun and let the gills absorb the sun, a gram will provide 20,000 IU. The mushrooms are so full of D, in fact, it’s important not to eat too many dried shiitakes, as vitamin D overdose can occur with chronic consumption of 40,000 IU of vitamin D per day.” http://www.rodalenews.com/growing-shiitake-mushrooms  also http://www.fungi.com/blog/items/place-mushrooms-in-sunlight-to-get-your-vitamin-d.html 
Vitamin C – add pine needle tea and dandelion to the article’s source list http://survivingtheoregontrail.com/blog/pine-needle-tea-high-in-vitamin-c-for-drink-antiseptic-uses-for-hair-and-body/ . The entire dandelion plant is edible, and the leaves contain vitamins A, C, and K, along with calcium, iron, manganese, and potassium. http://articles.mercola.com/sites/articles/archive/2012/04/08/the-five-healthiest-backyard-weeds.aspx 
Omega 3 – add wild Purslane as a good source for Omega 3. Purslane tops the list of plants with omega-3 fats.
Other healthy backyard “weeds” are:
Lamb’s-quarters. Lamb’s-quarters are like spinach, except healthier, tastier and easier to grow.
Plantain. Not the better-known banana-like plant with the same name. It has a nutritional profile similar to dandelion.
Stinging Nettles. If you handle them so that you don’t get a painful rash from the tiny, acid-filled needles, these are delicious and nutritious, cooked or prepared as a tea. – S.C.