# Is plant toxicity really an issue?



## GeoTerraTestudo (May 25, 2012)

A lot of people are interested in which plants may be toxic to tortoises. However, it seems that my tortoises only like to eat plants that are safe, and never try to eat more exotic fair. In captivity, some pet tortoises might not have a good diet, but that has more to do with safe foods in the wrong proportions, rather than plant toxicity. If pet tortoises eat too much fruit, for example, it's only because they encounter more than they would in the wild. And if they can't detect pesticides and herbicides, it's only because they have no evolutionary history with this chemicals. Moreover, tortoises can even detoxify some plants that would be dangerous for mammalian herbivores, such as sheep and horses, to consume. Thus, except for artificial chemicals and unnatural abundances of food, it seems that tortoises have excellent nutritional wisdom, and instinctively know what is good to eat, and what is not.

Given the above understanding of tortoise feeding behavior, I am a bit puzzled as to why people are concerned about tortoises' eating toxic plants. If it's safe to eat, they'll eat it. If not, not. Right? Maybe we should be more concerned with the right amounts of good plants to give them, rather than toxic plants. Has anyone out there ever actually had a tortoise or turtle become ill or die as a result of its eating a toxic plant?


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## JoesMum (May 25, 2012)

I will extend that. generally my tort will avoid all plants on the 'toxic' list, however he actively enjoys eating some others that are on the list (e.g. clematis and buterccup)

I think it is reasonable to assume that a tortoise's digestion does not work in the same way as ours. (After all many species cannot tolerate fruit like we can)

They do seem to know and, when they make mistakes, they don't seem to eat enough to do any damage.

I certainly have no qualms about anything growing in my garden and Joe is completely free range. 

Where I do think there is a risk is for those in more cramped quarters, be that indoors or out. With insufficient good stuff available, they may choose to eat more of the bad and that's when the damage is done. It's those picking plants to feed or planting up an enclosure that need to be aware most.


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## wellington (May 25, 2012)

I figure we need to be more careful about having toxic plants because they may normally not come across the kind we have. So they wouldn't know if they should eat it or not. I figure their native plants they would know which are to eat and which isn't. How many really have only their native plants. I would rather play it safe, as if it does make them sick, you may find out too late.


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## terryo (May 25, 2012)

I agree. I think if your tortoise or turtle garden is big enough and has enough plants for them to choose from, they'll do the right thing. But if you have a small pen, then you have to choose carefully. I've had box turtles for years, and so did my Dad. We've never watched what we planted and never had a sick boxie. My Cherry Head's garden is smaller, so I'm more careful about what I plant, although she rarely eats the plants, except for a few that she likes. Early in the Spring when the box turtles come out from hibernation, they will nibble on small sprouts coming up because worms and bugs are still scarce, but I believe they only eat what's OK for them.


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## Baoh (May 25, 2012)

I think the extent of concern I typically see expressed is far overblown and approaches paranoia.


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## GBtortoises (May 25, 2012)

For me there is no debate here. I agree with GeoTerra, JoesMum & terryo. I will go as so far to say that when I pick weeds for my tortoises which is nearly two full 33 gallon size trash bags about every 2-3 days, I pay little attention to what underlying weeds I am ripping out of the ground along with the known "safe" ones. I steer away from the very obvious known toxic weeds when I see them but there is no doubt that I pull up several of them when picking taller safe weeds. I've been doing that way for over 25 years and have yet to have a problem that could be attributed to them eating toxic plants. Some of my enclosures have Boxwood shrubs planted in them, a supposed known toxic plant. I planted them because they grown thick and low and provide good shade. My tortoises totally ignore them despite the plants having very green, very lush leaves within their reach. 
I'm a firm believer that they know more about what they can eat than we do.


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## Lulu (May 25, 2012)

I only care because mine mow things down so fast in their enclosures that I have to pick from the rest of the yard. I have a pretty limited set of stuff to choose from (mallow, chickweed, hawksbeard, etc.), so I just pull the stuff I know is good to give to them. I don't worry about the things they can access themselves because I agree they will probably only eat what they're supposed to eat. I care more about not wasting my time grabbing things they won't or shouldn't eat, and when I seed their enclosure (kind of pointless now in the hot season when they're eating like pigs and things grow slowly), I want to make sure I'm seeding with things they can eat.

That being said, I'm not going to plant something obviously toxic in their enclosure, like mother of millions. Livestock eat it and die, and arguably they should know better as well. I am going to research those things that I put into their environment, just to be on the safe side.


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## clare n (May 25, 2012)

All fair comments and a very insightful thread.
I asked the question regarding plants outside that are bad for my tortoise earlier today. Some of us are not experts, and have not been keeping tortoises even 1/10th of the time a lot of you all have, what research we do is often conflicted by different websites, full of mis leading information. (Hence why we join here.) People know what they can and shouldn't eat, that does not stop them- hence many peoples poor diets etc leading to health problems. Things that are bad for you are always the nicest. I simply asked if anyone uk wise had pointers on things to remove from the garden, if any, because I CARE. Now I know thanks to kind comments afterwards, and further pointers from yourselves. I'm rather unappreciative of the word "paranoid" I think those of us that do ask these questions are not "paranoid" just mis informed and given a lot of mixed information. In 40 years time I may look back and think... That was a stupid question.... But until then, many of us are new tortoise keepers that are trying to do our best.


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## JoesMum (May 25, 2012)

Clare, I don't want to take this off topic, but The Tortoise Table Plant Booklet should be your starting point


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## dmmj (May 25, 2012)

Personally I have never been a fan of the theory that tortoises don't eat what is not good for them. This maybe be a little OT but we all know of the stories of sulcatas, who eat just about anything they can get a hold of, mardi gras beads, plastic bags, dry wall, and the list goes on. I do know what may be toxic to mammals is not toxic to tortoises in general sometimes, but like I always say I would rather be safe than sorry.


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## clare n (May 25, 2012)

Thanks joesmum I'll give it a look 
wasn't having a go, I'm as happy as the next to let Phillip just get on n do his thing, I don't obsess over it and it certainly doesn't keep me up at night lol. Was just after pointers, gratefully received all by the way, read a few other people that asked the same question, just would like people to look back at the start of their hobbies- nobody is perfect  doesn't make us obsessive or paranoid, just eager to learn new things. Two years and I'm still learning every day.


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## Baoh (May 25, 2012)

clare n said:


> All fair comments and a very insightful thread.
> I asked the question regarding plants outside that are bad for my tortoise earlier today. Some of us are not experts, and have not been keeping tortoises even 1/10th of the time a lot of you all have, what research we do is often conflicted by different websites, full of mis leading information. (Hence why we join here.) People know what they can and shouldn't eat, that does not stop them- hence many peoples poor diets etc leading to health problems. Things that are bad for you are always the nicest. I simply asked if anyone uk wise had pointers on things to remove from the garden, if any, because I CARE. Now I know thanks to kind comments afterwards, and further pointers from yourselves. I'm rather unappreciative of the word "paranoid" I think those of us that do ask these questions are not "paranoid" just mis informed and given a lot of mixed information. In 40 years time I may look back and think... That was a stupid question.... But until then, many of us are new tortoise keepers that are trying to do our best.



I do not know you at all. If you do not take an approach that is paranoid in nature, then describing someone as paranoid does not apply to your situation.

However, if you thought it applied to you when I obviously spoke in a general sense, then you might...just...be...paranoid. The sentence preceding this one is a light joke, in case you could not tell. I would not want it to be misconstrued.


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## clare n (May 25, 2012)

Not taken badly at all, didnt take it personally,certainly won't ruin my day.  Just noticed it applied to quite a few similar questions posted in one day from other newer members such as myself,that's all. Just getting the point across that we are all here to learn, many people ask many questions and I read the occasional ones that get shot down in flames. All here for the same reasons, positive feedback is always more productive, whatever stage of the tortoise journey you are at  <3


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## JoesMum (May 25, 2012)

clare n said:


> Thanks joesmum I'll give it a look
> wasn't having a go, I'm as happy as the next to let Phillip just get on n do his thing, I don't obsess over it and it certainly doesn't keep me up at night lol. Was just after pointers, gratefully received all by the way, read a few other people that asked the same question, just would like people to look back at the start of their hobbies- nobody is perfect  doesn't make us obsessive or paranoid, just eager to learn new things. Two years and I'm still learning every day.


42 years and ditto


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## terryo (May 25, 2012)

I've had box turtles for over 30 years, and before that, my Dad had them. We never had a comptuer, so everything was trial and error, and going to the woods to observe what we could find. Now that we have computers, I'm so happy and I learn new things every day about box turtles. I'm also new to tortoises and only have mine 5 years. I think it's so great to come on here and other forums I belong to, and learn something new every day. IMHO, I don't think it matters how long you have your animals, you never stop learning. No one can possibly know everything.
I love this site and use it for my tortoise garden, all the time. Maybe it can help you too.

http://www.africantortoise.com/edible_landscaping.htm


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## yagyujubei (May 25, 2012)

If you go outside, get a handful of weeds, chop 'em up and mix with mazuri, I think it's important to know what you're adding to the food which will be eaten. Outside, I let them decide.


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## clare n (May 25, 2012)

I wish I had woods and places I could go to see them in their natural places  unfortunately the only times we see them here is crappy pet shops where they will sell them to anyone that walks in with a wad of cash, or the countries zoos. I could write an essay on what a sparrow does or next doors cat that insists on crapping in my garden, but the day I take a walk thru holland brook and see a tortoise "running" wild I will faint in shock


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## Baoh (May 25, 2012)

clare n said:


> Not taken badly at all, didnt take it personally,certainly won't ruin my day.  Just noticed it applied to quite a few similar questions posted in one day from other newer members such as myself,that's all. Just getting the point across that we are all here to learn, many people ask many questions and I read the occasional ones that get shot down in flames. All here for the same reasons, positive feedback is always more productive, whatever stage of the tortoise journey you are at  <3



No worries. I was not speaking about newbies. Some people have an OCD streak and are very concerned when routine is broken to the point they are (falsely) convinced disaster will occur from very minor changes that are really just insignificant. Play things safe when you are new to something. Once you have established a knowledge base and track record, feel free to branch out and seek the knowledge that caresheets and lists do not tend to provide. These latter tweaks can improve growth, reproduction, avoiding and managing illness, and more.


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## JoesMum (May 25, 2012)

Baoh said:


> No worries. I was not speaking about newbies. Some people have an OCD streak and are very concerned when routine is broken to the point they are (falsely) convinced disaster will occur from very minor changes that are really just insignificant. Play things safe when you are new to something. Once you have established a knowledge base and track record, feel free to branch out and seek the knowledge that caresheets and lists do not tend to provide. These latter tweaks can improve growth, reproduction, avoiding and managing illness, and more.



I agree whole heartedly


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## Madkins007 (May 25, 2012)

A few comments (you know me!  )

1. Nutritional wisdom. This refers to an animal's instinctive knowledge of what is good and bad to eat- in captivity. Tortoises are considered to have poor nutritional wisdom insofar as they will often eat whatever garbage is available no matter how poor it is for them nutritionally (if they had good nutritional wisdom, they would not get MBDs so easily). Of course, since they can eat such a wide variety of foods and mostly live in places with such a poor selection of available options, they really don't need a lot of nutritional wisdom.

2. Plant toxicity. This is closely related to the above. Tortoises can eat a ton of stuff that will flat out kill a human and most mammals. MOST of the plants on toxic lists get there by being dangerous to some degree to humans, pets, and domestic animals. Only a few plants are widely considered really dangerous to tortoises- things like oak, lily, foxglove, oleander, and tobacco are the top of the list. 

3. A lot of the plants on toxic lists just plain taste horrible! The reason they evolved toxins is to keep things from eating them! MOST of these plants taste bitter, soapy, 'sharp', or just plain nasty. Tortoises may not have high nutritional wisdom, but that does not make them stupid enough to not taste the things designed to warn them off.

So... yeah. Most of the paranoia over 'is this safe?' is unfounded. But then again, I think most of the paranoia over goiterinogens, oxalates, purines, etc. is unfounded as well.


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## Kristina (May 25, 2012)

You know, I don't worry about it much. I'm not going to go out and plant something that I know is horrdily toxic like deadly nightshade in my enclosures, but at the same time, I'll plant just about anything that catches my eye and fits in with the theme of the enclosure. Not every single plant that tortoises come across in the wild are non-toxic. They HAVE to have some instinctive knowledge about what is edible and what is not. If they didn't, there wouldn't be many tortoises, lol.

A lot of the plants that are in my "forest" enclosures (Box turtles, Redfoots, Manouria, Hingebacks) are plants that I collect out of the woods. (Always be sure not to take every plant of any species from one given spot, leave some to reproduce for the next year, and only collect out of areas that you know are not sprayed or otherwise treated with chemicals.) Very few of them are on the lists of toxic/non-toxic plants. However, they create the environment that I want for my tortoises, and are very easy for my to care for. They thrive well without excessive work.


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## Tom (May 25, 2012)

Addressing the original post:

Haha. You've never had a sulcata have you GTT? (said with a devilish smirk...)

Sure in the wild with 100s of square miles and all sorts of seasonal variations and 1000s (or more) of plant species to choose from, they make good decisions. Put that same animal in a bare dirt pen feed him light for "slow growth", which is often advocated, and after a few months of feeling like they are starving, and they will eat ANYTHING that falls or blows into their pen. I see this sort of thing with all captive animals, not just tortoises. So do vets. Ask a vet what sort of things they've pulled out of animals and tortoises. I once had to stop one of my sulcatas from eating oleander. Had to pull it out of his mouth.

The bottom line is that in a large, well planted enclosure, with abundant food, they will usually make good decisions as we have all witnessed. But I think some of us at least, have also witnessed them eating things they shouldn't. Sometimes a captive situation will do funny things to an animals mind and cause them to do things that they normally would not. I once watched an ostrich panic and pull his own head off. I've seen horses freak out and run straight into a wall and break their own neck. I've seen all sorts of animals eat all sorts of things they shouldn't. For me, "usually" is not good enough. If they don't have access to a toxic plant, they can NEVER eat it, no mater what.


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## Terry Allan Hall (May 26, 2012)

GeoTerraTestudo said:


> A lot of people are interested in which plants may be toxic to tortoises. However, it seems that my tortoises only like to eat plants that are safe, and never try to eat more exotic fair. In captivity, some pet tortoises might not have a good diet, but that has more to do with safe foods in the wrong proportions, rather than plant toxicity. If pet tortoises eat too much fruit, for example, it's only because they encounter more than they would in the wild. And if they can't detect pesticides and herbicides, it's only because they have no evolutionary history with this chemicals. Moreover, tortoises can even detoxify some plants that would be dangerous for mammalian herbivores, such as sheep and horses, to consume. Thus, except for artificial chemicals and unnatural abundances of food, it seems that tortoises have excellent nutritional wisdom, and instinctively know what is good to eat, and what is not.
> 
> Given the above understanding of tortoise feeding behavior, I am a bit puzzled as to why people are concerned about tortoises' eating toxic plants. If it's safe to eat, they'll eat it. If not, not. Right? Maybe we should be more concerned with the right amounts of good plants to give them, rather than toxic plants. Has anyone out there ever actually had a tortoise or turtle become ill or die as a result of its eating a toxic plant?





GBtortoises said:


> For me there is no debate here. I agree with GeoTerra, JoesMum & terryo. I will go as so far to say that when I pick weeds for my tortoises which is nearly two full 33 gallon size trash bags about every 2-3 days, I pay little attention to what underlying weeds I am ripping out of the ground along with the known "safe" ones. I steer away from the very obvious known toxic weeds when I see them but there is no doubt that I pull up several of them when picking taller safe weeds. I've been doing that way for over 25 years and have yet to have a problem that could be attributed to them eating toxic plants. Some of my enclosures have Boxwood shrubs planted in them, a supposed known toxic plant. I planted them because they grown thick and low and provide good shade. My tortoises totally ignore them despite the plants having very green, very lush leaves within their reach.
> I'm a firm believer that they know more about what they can eat than we do.



Agreed...I've never seen any of my tortoises eat a plant that was toxic to them, although I know my daughter's Box Turtles love to eat mushrooms that would kill me (an amusing, if perhaps not absolutely PC anecdote: In the early days of White/Cherokee relations - around the early 1700s - if my ancestors liked you, they'd tell you why they do not eat box turtles, but if they didn't, they'd still leave a string of beads to help you on your way to _*The Land Afterwards*_...)


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## GeoTerraTestudo (May 27, 2012)

Madkins007 said:


> 1. Nutritional wisdom. This refers to an animal's instinctive knowledge of what is good and bad to eat- in captivity. Tortoises are considered to have poor nutritional wisdom insofar as they will often eat whatever garbage is available no matter how poor it is for them nutritionally (if they had good nutritional wisdom, they would not get MBDs so easily). Of course, since they can eat such a wide variety of foods and mostly live in places with such a poor selection of available options, they really don't need a lot of nutritional wisdom.



Great comments, Mark. However, when it comes to nutritional wisdom, I rank turtles pretty highly. These animals have no evolutionary experience with plastic bottle caps or other kinds of garbage, so it should come as no surprise that they might try to eat them. However, with respect to things they have evolved to recognize, like plants, fruits, and invertebrates, they seem to be very good at knowing what's worth trying and what isn't.

As for MBD, I think a lot of reptiles get it in captivity, simply because the conditions are so different from what they really need. Whether it's a lizard, a turtle, or a crocodilian, reptiles need plenty of calcium and vitamin D3 in their diet and from basking. It's not the reptile's fault if his keeper doesn't know what to feed him, or what kind of environment to provide. Some turtles get MBD because their keepers keep them in a 10-gallon tank and only feed them iceberg lettuce, and there's really not much the turtle can do about that. Iceberg lettuce is not toxic, so they eat it. Obviously, they need a much more diverse and nutritious diet than that, as well as a better environment, including UVB and hopefully time outdoors. But the MBD doesn't come from poor nutritional wisdom, it comes from poor husbandry.






Tom said:


> Haha. You've never had a sulcata have you GTT? (said with a devilish smirk...)
> 
> The bottom line is that in a large, well planted enclosure, with abundant food, they will usually make good decisions as we have all witnessed. But I think some of us at least, have also witnessed them eating things they shouldn't.



LOL ... point taken. Sounds like, if a tortoise is hungry enough, and is able to get into all sorts of strange things, who knows what it might end up eating?


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## Tom (May 27, 2012)

GeoTerraTestudo said:


> LOL ... point taken. Sounds like, if a tortoise is hungry enough, and is able to get into all sorts of strange things, who knows what it might end up eating?



Right. I consider most of the regular posters here a pretty elite group. Very experienced and knowledgeable. Even though we may disagree and use different methods, I think we all maintain excellent enclosure, feed a healthy diet, and do the right things necessary to maintain healthy tortoises. As an animals professional for the last 26 years, I have also seen the "other" side. I have seen many sad situations involving complete ignorance and or apathy, and lots of dead or dying tortoises. When we (the regular posters) talk on this forum, I think in most cases we can assume the best, and there is a lot that is just understood among us. I don't think your average tortoise keeper out there keeps their enclosures as well as TerryO or Terry AH. I don't think Dennis or Mark or Kristina or JD or ANY of our regulars could be considered anywhere even remotely near "average". It does not surprise me that EXTREMELY well cared for and well fed tortoise are not eating the wrong things. I'm just saying, that this is a different discussion if we are talking about the "average" tortoise keeper out in the world. Comparing one of of Kristina's (just for example) awesome super healthy tortoises to one of my neighbors tortoises kept on bare dirt in a plain, undecorated in any way, rectangular pen, is two TOTALLY different things. I would expect to see different things with each animal.


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## CLMoss (May 27, 2012)

I would be very careful...


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## Jacqui (May 27, 2012)

I am mixed on this point. I think the "normal" tortoise, will know which plants not to eat if they are native to his natural environment. I think some however will eat things not native to them or eat them because they are hungry or even bored, those behaviors can lead them into problems.

When I plant anything into one of my enclosures I look at what animal will be housed there. I know for instance my hingebacks will rarely touch anything in their enclosures, so any plant is pretty safe for them. Now if we are talking the Russians, no plant is safe with them as they eat everything. This means I won't be planting something like tomatoes in their enclosures.  If your talking a very small youngster, with their small body mass, even a little bit of something can have big consequences for them, so I am more careful with them. However with the larger two sulcata with their bigger body mass, I really don't worry much about them. So for me how "paranoid" I am depends on what species, it's eating habits, and it's body mass. I also don't go with what the "lists" say are toxic, I do more asking around and go by the experience of others, too.


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## LeaderLeprechaun (May 28, 2012)

Tbh Im glad this thread popped up. I know that personally Im borderline with "being on the safe side" and letting the torts pick for themselves. Being an Environmental Biology major with studies in animal behavior Ive noticed that animals overall know what they should and shouldnt eat, so I do agree with this point of view. However, I do also agree that those animals which are captive bred may not entirely understand what is good or bad due to not being exposed to it before. In my personal opinion, finding that my tort was not captive bred I tred on both sides. I have looked at the tortoisetable sites as well as many others to decides what can and cannot be fed or in the terrarium. This is a good topic though and Im personally glad it was brought up.


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