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June 23[edit]

Rhododendrons, Camellias, and Magnolias[edit]

Is there an easy way to distinguish between rhododendrons, camellias, and magnolias? I tend to get them confused at times. DuncanHill (talk) 00:49, 23 June 2015 (UTC)[reply]

Yes the flowers will do it. Camellias also tend not to repeat flower while magnolias do. Camellias and magnolias tend to flower before rhododendrons (as a rule of thumb, if you see a rhododendron in flower when the magnolia is, it's an azalea). Camellia flowers tend to be more spheroid in form with rounded petals, rhododendrons flower in clusters and the flowers are more trumpet-like, and magnolias flower singly and their flowers tend to have thinner, more pointed petals. Having said all that, there is a great deal of variation within each species and it can be very hard to tell which is which at times. --TammyMoet (talk) 04:40, 23 June 2015 (UTC)[reply]

Are you looking for more rules of thumb, or do you want a Identification_key that covers this? I'm assuming the former (as keys are hard to use and generally people don't like them). Tammy's advice is good. I'll add that magnolias are older than bees! - and this shows in their flower - very tough carpels and buds compared to the others. Also, rhodos don't really ever get bigger than "shrub" sized, while magnolias can tower over a courtyard. If it's over ~30 ft, it's probably not a rhodo. Also all camellias are evergreen, while some magnolias are deciduous. Rhodos can go either way too, but usually in my experience only the evergreen type are planted ornamentally. If you see one not in bloom and not in winter, you'll have to start looking at leaf margin, leaf veination and other stuff like that to be sure. If you do want a rigorous key, I can probably help with that too. SemanticMantis (talk) 13:55, 23 June 2015 (UTC)[reply]

Thank you both. A rule of thumb is pretty much what I came here for, but a key would be great. I'm particularly interested in those that grow in Cornwall (both wild and domesticated), where of course many plants stay in leaf much longer than in less temperate climes. DuncanHill (talk) 14:00, 23 June 2015 (UTC)[reply]

I'm not so good for UK plants, but here is a fun group of the RHS you could check out [1], and here's a nice Cornwall-specific site that might be of interest [2]. As for keys, I'm not finding anything that great at the moment, but this one [3] is at least fairly easy to use. I didn't walk through this one [4], but it is at least better designed for web use. SemanticMantis (talk) 14:32, 23 June 2015 (UTC)[reply]

Rhododendrons and azaleas are vaguely similar to camellias. Magnolias are quite different, in that they have what I call "leathery" leaves and petals. ←Baseball Bugs ^{What's up, Doc?} carrots→ 15:18, 23 June 2015 (UTC)[reply]

Not all of them. The American tulip tree (commonly called "Yellow Poplar" or "Tulip Poplar"), though no relation to true poplars) is a very common hardwood tree in the American Southeast and Midwest, especially around me in North Carolina, and it is actually from the magnolia family. The leaves are more reminiscent of a simplified maple leaf, not at all like the leathery leaves of the classic Magnolia virginiana or Magnolia grandiflora which are the classic ornamental Magnolias found around the U.S. The flower and seed pods of the tulip trees are close to other magnolias, so I would say that's the class way to identify most magnolias, not necessarily the leathery leaves, which are most common in popular ornamental varieties (and thus well known to many suburban homeowners) but not necessarily in all wild species. The tulip tree is a common timber tree, rather than ornamental, so it isn't perhaps as well known. --Jayron 32 01:45, 24 June 2015 (UTC)[reply]

Cassava as food.[edit]

Could you direct me to information about how a people learn to modify a food stuff to render it edible instead of just forgetting about it when upon first eating it makes them sick? — Preceding unsigned comment added by 174.100.9.181 (talk) 13:35, 23 June 2015 (UTC)[reply]

Cassava#History. References 11 and 12 specifically describe early consumption by humans, and the rise of cassava agriculture. Here's another summary from University of Colorado: CU Team discovers Mayan crop system. Nimur (talk) 13:57, 23 June 2015 (UTC)[reply]

One method is Trial_and_error. I mean who would have thought 10,000 years ago you could get a low glycoalkaloid content "by leaving potatoes out in the open, where they are frozen at night, stomped underfoot and dried in the sun for many days"? http://wholehealthsource.blogspot.com/2010/09/potatoes-and-human-health-part-i.html Remember the old saying for mushrooms: There are OLD mushroom eaters and there are BOLD mushroom eaters but not old bold mushroom eaters. 196.213.35.146 (talk) 14:05, 23 June 2015 (UTC)[reply]

I wonder if there is a page somewhere on Wikipedia about foods that are poisonous before they have been processed. There's so many things people eat like that. I suppose it isn't so strange after seeing the discussions above, after all people eat rotting meat and drink quinine. Dmcq (talk) 14:31, 23 June 2015 (UTC)[reply]

Good point. A WP page may be of interest on this subject as there are a lot of common foods that need preprocessing. Do you want to start it off? Examples could include mushroom that give off cyanide during frying, bitter almonds, cashews, kidney beans, caster oil, cotton oil, rhubarb leaves, escargot, et cetera. There is quite a list. Editor Medais could also help, as she is a bit of a know-it-all when it comes to food.--Aspro (talk) 19:52, 23 June 2015 (UTC)[reply]

I'm not seeing any grouping like that, but it would be fun to start! Hákarl is an interesting one (make sure you start with a rotten shark, it's safer!), but it would be tricky deciding group inclusion. After all the dose makes the poison, and things like onions and garlic contain compounds that are harmful in high doses. Here's a similar list [5], some of them are literally poisonous before processing, while others like the tomato are just fruits that come from plants whose stems and leaves we shouldn't eat. SemanticMantis (talk) 14:43, 23 June 2015 (UTC)[reply]

I think a fair amount of intelligence goes into it, too. People observed animals eating those things, so concluded that there must be nutrition in them, but got sick when they ate them, so then tried various ways to prepare them. (Now they may have thought they were trying to find a way to "drive out the demons", but that didn't matter, only the results did.) StuRat (talk) 19:58, 23 June 2015 (UTC)[reply]