I got curious so I decided to do a little light research on some spring mix ingredients. Since so many people use it to supplement their tortoises diets. This is what the one I looked up had in it (I think it is called the Italian style)-- so No spinach in it.); Red and Green Romaine, Red & Green Oak leaf, Red Leaf, Lollo Rosa, Tango, Organic Red & Green Chard, Organic Mizuna, Organic Arugula, Organic Mache, Organic Frisee, Organic Radicchio.
So we have two types of lettuce Romaine (cos) and looseleaf, totaling 6 varieties of lettuce ( low nutritional values).
We have swiss chard in two colors (Red and Green) which contain oxalic acid.
Two from the Brassicaceae Family (arugala and Mizuna) both contain glucosinolates (goiter causing substances).
And two from the Common Chicory family (Frisée and Radicchio) which have glycosides.
Now if I have really wet your ppetite for more information on these ingredients keep reading.
It is Really, Really long from here and gets somewhat technical in places but there is some interesting reading and a couple of links if you care to continue.
Now let's look at what we really have;
Lettuce;
Red and Green Romaine, Red & Green Oak leaf, Red Leaf, Lollo Rosa, Mache and Tango
Romaine or cos lettuce (Lactuca sativa L. var. longifolia) is a variety of lettuce which grows in a long head of sturdy leaves with a firm rib down the center. Unlike most lettuces, it is tolerant of heat.
Loose Leaf Lettuce (Lactuca sativa) (This is Tango,). is a temperate annual or biennial plant of the daisy family Asteraceae. It is most often grown as a leaf vegetable. In many countries, it is typically eaten cold, raw, in salads, sandwiches, hamburgers, tacos, and in many other dishes. In some places, including China, lettuce is typically eaten cooked and use of the stem is as important as use of the leaf.
This is Lollo Rosa = Lactuca sativa. Plant produces flavorful leaf type lettuce. Leaves are green with frilly red edges tips. Excellent for salads and garnishes. Slow to bolt.
This is Oak Leaf = Lactuca sativa. Plant produces very flavorful medium dark lettuce that are shaped like oak leaves. As outer leaves are picked, inner leaves keep producing. Excellent for salads and garnishes. This variety stands well without bolting. Long standing, never bitter and does amazingly well in summer heat.
This is Red leaf = Lactuca sativa. Early variety produces flavorful red leaf lettuce. As outer leaves are picked, inner leaves keep producing.
There are six commonly recognised Cultivar Groups of lettuce which are ordered here by head formation and leaf structure; there are hundreds of cultivars of lettuce selected for leaf shape and colour, as well as extended field and shelf life, within each of these Cultivar Groups:
• Butterhead forms loose heads. Its leaves have a buttery texture. Butterhead cultivars are most popular in Europe. Popular varieties include Boston, Bibb, Buttercrunch, and Tom Thumb.
• Chinese lettuce types generally have long, sword-shaped, non-head-forming leaves, with a bitter and robust flavour unlike Western types, for use in stir-fried dishes and stews. Chinese lettuce cultivars are divided into “stem-use†types (called celtuce in English) called wosun (Chinese: 莴笋; pinyin: wÃ…ÂsÃ…Ân) or woju (Chinese: 莴苣; pinyin: wÃ…Âjù) (although the latter name may also be used to mean lettuce in general)., and “leaf-use†types such as youmaicai (Chinese: 油麦èÂÅ“; pinyin: yóumàicài) or shengcai (çâ€Å¸Ã¨ÂÅ“).
• Crisphead, also called Iceberg, forms tight, dense heads that resemble cabbage. They are generally the mildest of the lettuces, valued more for their crunchy texture than for flavour. Cultivars of iceberg lettuce are the most familiar lettuces in the USA. The name Iceberg refers to the crisp, cold, clean characteristics of the leaves.
• Looseleaf (also called leaf lettuce) has tender, delicate, and mildly flavoured leaves. This group includes oak leaf and lollo rosso lettuces.
• Romaine, also called Cos, grows in a long head of sturdy leaves with a firm rib down the center. Unlike most lettuces, it is tolerant of heat.
• Summer Crisp, also called Batavian, forms moderately dense heads with a crunchy texture. This type is intermediate between iceberg and looseleaf types.
Some lettuces (especially iceberg) have been specifically bred to remove the bitterness from their leaves. These lettuces have a high water content with very little nutrient value. The more bitter lettuces and the ones with pigmented leaves contain antioxidants.
Nutrition of Lettuce
Lettuce is a fat free, low calorie food and is good for a well balanced diet. It is a valuable source of vitamin A and folic acid. Lactucarium (or “Lettuce Opiumâ€Â) is a mild opiate-like substance that is contained in all types of lettuce. Both the Romans and Egyptians took advantage of this property eating lettuce at the end of a meal to induce sleep.
An example of Nutritional values:
Romaine lettuce
Nutritional value per 100 g (3.5 oz)
Energy 20 kcal 70 kJ
Carbohydrates 3.3 g
Dietary fiber 2.1 g
Fat 0.3g
Protein 1.2 g
Water 95g
Vitamin A equiv. 290 μg
Folate (Vit. B9) 136 μg
Vitamin C 24 mg
Calcium 33 mg
Iron 0.97 mg
Potassium 247 mg
Nutrition Facts (One cup raw leaf lettuce, chopped)
Calories 9
Dietary Fiber 1.3
Protein 1 gram
Carbohydrates 1.34 grams
Vitamin A 1456 IU
Vitamin C 13.44
Calcium 20.16
Iron 0.62
Potassium 162.4 mg
Chard:
Red & Green
Family: Amaranthaceae
Genus: Beta
Species: B.vulgaris
Sub species: B.v.var.cicla
Trinominal name: Beta vulgaris var.cicla
also known by the common names Swiss Chard[1], Silverbeet, Perpetual Spinach, Spinach Beet, Crab Beet, Seakale Beet and Mangold, is a leafy vegetable and a Beta vulgaris subsp. maritima. Although the leaves are eaten, it is in the same species as the garden beet (beetroot) which is usually grown primarily for its edible roots. Cultivars of chard include green forms, such as 'Lucullus' and 'Fordhook Giant', as well as red-ribbed forms such as 'Ruby Chard', 'Rainbow Chard', and 'Rhubarb Chard'. All parts of the chard plant contain oxalic acid.
Nutritional values slightly unfair as this is for boiled.
http://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=72
Brassicaceae Family
Arugula
Family: Brassicaeae
Genus: Eruca
Species: E.Sativa
Binominal Name
Eruca sativa
Eruca sativa (syn. E. vesicaria subsp. sativa (Miller) Thell., Brassica eruca L.), also known as rocket or arugula, is an edible plant. It is a species of Eruca native to the Mediterranean region, from Morocco and Portugal east to Lebanon and Turkey.
Vernacular names include Garden Rocket, Rocket (British English), Eruca, Rocketsalad, Arugula (American English), Rucola (Italian)[[8], Rukola (Macedonian, Serbian, Slovenian, Polish), Rugola (Italian), Rauke (German), Roquette (French), Rokka (Greek), Roka (Turkish), Ruca (Catalan), Beharki (Basque), Voinicică (Romanian) Rúcula, Oruga and Arúgula (Spanish), Rúcula (Portuguese), Ruchetta (Italian) and Rughetta (Italian).
Nutitional values http://www.nutritiondata.com/facts/vegetables-and-vegetable-products/3025/2
Mizuna
Family: Brassicaeae
Genus: Eruca
Species: B. rapa
also called Xiu Cai, Kyona, Japanese Mustard, Potherb Mustard, Japanese Greens, California Peppergrass, Spider Mustard, etc.)
In addition to the term "mizuna" (and its alternates) being applied to at least two different species of Brassica, horticulturalists have defined and named a number of varieties. For example, a resource provided by Cornell University and the United States Department of Agriculture lists sixteen varieties including "Early Mizuna", "Kyona Mizuna", "Komatsuna Mizuna", "Vitamin Green Mizuna", "Kyoto Mizuna", "Happy Rich Mizuna", "Summer Fest Mizuna", "Tokyo Early Mizuna", "Mibuna Mizuna", "Red Komatsuna Mizuna", "Waido Mizuna" and "Purple Mizuna".
One fast-growing variety called "Organic Early Mizuna Mustard Salad Greens" by its Indiana-based seller reaches maturity in 48 days at 12 - 24†tall
Mizuna is a mild mustard green. Also known as Spider Mustard, its scientific name is Brassica rapa, which indicates it is related to broccoli and cabbage, with similar nutritional value. And like other brassica vegetables, it contains glucosinolates.
...contains vitamin C, folic acid, and antioxidants. And like other brassica vegetables, it contains glucosinolates, which may inhibit the development of certain cancers. Glucosinolates are the compounds that give brassicas, like Brussels sprouts and cabbage, their bitter flavor. Cultivated varieties of Brassica rapa include:
• Chinese cabbage: Bok choi (chinensis group) and Napa cabbage (pekinensis group)
• Mizuna (nipposinica group)
• Aburana (nippo-oleifera group)
• Flowering cabbage (parachinensis group)
• Turnip (rapa group)
• Turnip rape (Brassica rapa subsp. oleifera) [2]
• Rapini (ruvo group)
• Tatsoi
• Komatsuna
Mustard Greens: 104mg - 58 mg ratio of 1.8:1
Nutritional info on mustard though this is also boiledhttp://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=36
See other Cruciferous vegitables
http://en.wikipedia.org/wiki/Cruciferous_vegetables
Chicory Family:
Endive:
Family: Asteraceae
Genus: Cichorium
Species: C endivia
Binominal Name: Cichorium endivia
Frisee and Radicchio
Family: Asteraceae
Tribe: Cichorieae
Genus: Cichorium
Species: C. intybus
Binominal Name: Cichorium intybus
Endive belongs to the chicory genus, which includes several similar bitter leafed vegetables. Species include endive (Cichorium endivia), Cichorium pumilum and common chicory (Cichorium intybus). Common chicory includes chicory types such as radicchio, puntarelle and Belgian endive.
Endive is rich in many vitamins and minerals, especially in folate and vitamins A and K, and is high in fiber.
There are two main varieties of cultivated endive:
Frisée
• Curly endive, or frisée (var crispum). This type has narrow, green, curly outer leaves. Sometimes called chicory in the United States and is called chicorée frisée in French. Further confusion results from the fact that frisée also refers to a technique in which greens are lightly wilted with oil.
• Escarole, or broad-leaved endive (var latifolia) has broad, pale green leaves and is less bitter than the other varieties. Varieties or names include broad-leaved endive, Bavarian endive, Batavian endive, grumolo, scarola and scarole.
Common chicory (Cichorium intybus) is a bushy perennial herb with blue, lavender, or occasionally white flowers. It grows as a wild plant on roadsides in its native Europe, and in North America and Australia, where it has become naturalized. Common chicory is also known as blue sailors, succory, and coffeeweed. It is also called cornflower, although that name is more properly applied to Centaurea cyanus. The cultivated forms are grown for their leaves (var. foliosum), or for the roots (var. sativum), which are baked, ground, and used as a coffee substitute and additive. Common names for varieties of var. foliosum include endive, radicchio, Belgian endive, French endive, red endive, sugarloaf or witloof.
Chicory is also the common name in the US (and in France) for curly endive (Cichorium endivia). There is considerable confusion between Cichorium endivia and Cichorium intybus.
Leaf chicory
Chicory may be grown for its leaves, eaten raw as a salad. It is generally divided into three types of which there are many varieties
• Radicchio usually has variegated red or red and green leaves. Some only refer to the white-veined red leaved type as radicchio. Also known as red endive and red chicory. It has a bitter and spicy taste, which mellows when it is grilled or roasted. It can also be used to add color and zest to salads.
• Sugarloaf looks rather like cos lettuce, with tightly packed leaves.
• Belgian endive is also known as French endive, witlof in the Netherlands, witlo(o)f in the USA, chicory in the UK, as witlof in Australia, endive in France, and chicon in parts of Northern France and in Wallonia. It has a small head of cream-coloured, bitter leaves. It is grown completely underground or indoors in the absence of sunlight in order to prevent the leaves from turning green and opening up (etiolation). Not suggested for tortoise diet.
Although leaf chicory is often called "endive", true endive (Cichorium endivia) is a different species in the genus.
The bitter substances are primarily the two sesquiterpene lactones Lactucin and Lactucopicrin. Other ingredients are Aesculetin, Aesculin, Cichoriin, Umbelliferone, Scopoletin and 6.7-Dihydrocoumarin and further sesquiterpene lactones and their glycosides.
http://en.wikipedia.org/wiki/Glycoside
Calcium & Phosphorous Content of Common Vegetables & Fruits http://www.swanimalhospital.net/html/veggie_info.html
Some information from:
http://plants.usda.gov/java/profile?symbol=LACTU
http://www.reimerseeds.com/lollo-rosa-lettuce.aspx
http://urbanext.illinois.edu/veggies/lettuce1.html
http://en.wikipedia.org
Most plants carry what we look at as toxins of some sort. What we need to remember is the amount that is in the plant and the amount we feed to our animals. Some people would prefer to steer clear of Oxalic acid, others glucosinolates, or glycosides, or high protiens, or tannins, etc. I do not think we have yet gotten down to a science how to feed our tortoises regarding the amount of which toxin is infact harmful to them. So we feed a variety of greens to minimize the risk of concentrating one toxin or another. Each keeper needs to decide what and how they are going to provide a diet for their particular species. Because not only are their toxins in all plants but the amount can vary depending on how it is grown, time of harvesting, etc.
The information given here is stricly to inform.
So we have two types of lettuce Romaine (cos) and looseleaf, totaling 6 varieties of lettuce ( low nutritional values).
We have swiss chard in two colors (Red and Green) which contain oxalic acid.
Two from the Brassicaceae Family (arugala and Mizuna) both contain glucosinolates (goiter causing substances).
And two from the Common Chicory family (Frisée and Radicchio) which have glycosides.
Now if I have really wet your ppetite for more information on these ingredients keep reading.
It is Really, Really long from here and gets somewhat technical in places but there is some interesting reading and a couple of links if you care to continue.
Now let's look at what we really have;
Lettuce;
Red and Green Romaine, Red & Green Oak leaf, Red Leaf, Lollo Rosa, Mache and Tango
Romaine or cos lettuce (Lactuca sativa L. var. longifolia) is a variety of lettuce which grows in a long head of sturdy leaves with a firm rib down the center. Unlike most lettuces, it is tolerant of heat.
Loose Leaf Lettuce (Lactuca sativa) (This is Tango,). is a temperate annual or biennial plant of the daisy family Asteraceae. It is most often grown as a leaf vegetable. In many countries, it is typically eaten cold, raw, in salads, sandwiches, hamburgers, tacos, and in many other dishes. In some places, including China, lettuce is typically eaten cooked and use of the stem is as important as use of the leaf.
This is Lollo Rosa = Lactuca sativa. Plant produces flavorful leaf type lettuce. Leaves are green with frilly red edges tips. Excellent for salads and garnishes. Slow to bolt.
This is Oak Leaf = Lactuca sativa. Plant produces very flavorful medium dark lettuce that are shaped like oak leaves. As outer leaves are picked, inner leaves keep producing. Excellent for salads and garnishes. This variety stands well without bolting. Long standing, never bitter and does amazingly well in summer heat.
This is Red leaf = Lactuca sativa. Early variety produces flavorful red leaf lettuce. As outer leaves are picked, inner leaves keep producing.
There are six commonly recognised Cultivar Groups of lettuce which are ordered here by head formation and leaf structure; there are hundreds of cultivars of lettuce selected for leaf shape and colour, as well as extended field and shelf life, within each of these Cultivar Groups:
• Butterhead forms loose heads. Its leaves have a buttery texture. Butterhead cultivars are most popular in Europe. Popular varieties include Boston, Bibb, Buttercrunch, and Tom Thumb.
• Chinese lettuce types generally have long, sword-shaped, non-head-forming leaves, with a bitter and robust flavour unlike Western types, for use in stir-fried dishes and stews. Chinese lettuce cultivars are divided into “stem-use†types (called celtuce in English) called wosun (Chinese: 莴笋; pinyin: wÃ…ÂsÃ…Ân) or woju (Chinese: 莴苣; pinyin: wÃ…Âjù) (although the latter name may also be used to mean lettuce in general)., and “leaf-use†types such as youmaicai (Chinese: 油麦èÂÅ“; pinyin: yóumàicài) or shengcai (çâ€Å¸Ã¨ÂÅ“).
• Crisphead, also called Iceberg, forms tight, dense heads that resemble cabbage. They are generally the mildest of the lettuces, valued more for their crunchy texture than for flavour. Cultivars of iceberg lettuce are the most familiar lettuces in the USA. The name Iceberg refers to the crisp, cold, clean characteristics of the leaves.
• Looseleaf (also called leaf lettuce) has tender, delicate, and mildly flavoured leaves. This group includes oak leaf and lollo rosso lettuces.
• Romaine, also called Cos, grows in a long head of sturdy leaves with a firm rib down the center. Unlike most lettuces, it is tolerant of heat.
• Summer Crisp, also called Batavian, forms moderately dense heads with a crunchy texture. This type is intermediate between iceberg and looseleaf types.
Some lettuces (especially iceberg) have been specifically bred to remove the bitterness from their leaves. These lettuces have a high water content with very little nutrient value. The more bitter lettuces and the ones with pigmented leaves contain antioxidants.
Nutrition of Lettuce
Lettuce is a fat free, low calorie food and is good for a well balanced diet. It is a valuable source of vitamin A and folic acid. Lactucarium (or “Lettuce Opiumâ€Â) is a mild opiate-like substance that is contained in all types of lettuce. Both the Romans and Egyptians took advantage of this property eating lettuce at the end of a meal to induce sleep.
An example of Nutritional values:
Romaine lettuce
Nutritional value per 100 g (3.5 oz)
Energy 20 kcal 70 kJ
Carbohydrates 3.3 g
Dietary fiber 2.1 g
Fat 0.3g
Protein 1.2 g
Water 95g
Vitamin A equiv. 290 μg
Folate (Vit. B9) 136 μg
Vitamin C 24 mg
Calcium 33 mg
Iron 0.97 mg
Potassium 247 mg
Nutrition Facts (One cup raw leaf lettuce, chopped)
Calories 9
Dietary Fiber 1.3
Protein 1 gram
Carbohydrates 1.34 grams
Vitamin A 1456 IU
Vitamin C 13.44
Calcium 20.16
Iron 0.62
Potassium 162.4 mg
Chard:
Red & Green
Family: Amaranthaceae
Genus: Beta
Species: B.vulgaris
Sub species: B.v.var.cicla
Trinominal name: Beta vulgaris var.cicla
also known by the common names Swiss Chard[1], Silverbeet, Perpetual Spinach, Spinach Beet, Crab Beet, Seakale Beet and Mangold, is a leafy vegetable and a Beta vulgaris subsp. maritima. Although the leaves are eaten, it is in the same species as the garden beet (beetroot) which is usually grown primarily for its edible roots. Cultivars of chard include green forms, such as 'Lucullus' and 'Fordhook Giant', as well as red-ribbed forms such as 'Ruby Chard', 'Rainbow Chard', and 'Rhubarb Chard'. All parts of the chard plant contain oxalic acid.
Nutritional values slightly unfair as this is for boiled.
http://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=72
Brassicaceae Family
Arugula
Family: Brassicaeae
Genus: Eruca
Species: E.Sativa
Binominal Name
Eruca sativa
Eruca sativa (syn. E. vesicaria subsp. sativa (Miller) Thell., Brassica eruca L.), also known as rocket or arugula, is an edible plant. It is a species of Eruca native to the Mediterranean region, from Morocco and Portugal east to Lebanon and Turkey.
Vernacular names include Garden Rocket, Rocket (British English), Eruca, Rocketsalad, Arugula (American English), Rucola (Italian)[[8], Rukola (Macedonian, Serbian, Slovenian, Polish), Rugola (Italian), Rauke (German), Roquette (French), Rokka (Greek), Roka (Turkish), Ruca (Catalan), Beharki (Basque), Voinicică (Romanian) Rúcula, Oruga and Arúgula (Spanish), Rúcula (Portuguese), Ruchetta (Italian) and Rughetta (Italian).
Nutitional values http://www.nutritiondata.com/facts/vegetables-and-vegetable-products/3025/2
Mizuna
Family: Brassicaeae
Genus: Eruca
Species: B. rapa
also called Xiu Cai, Kyona, Japanese Mustard, Potherb Mustard, Japanese Greens, California Peppergrass, Spider Mustard, etc.)
In addition to the term "mizuna" (and its alternates) being applied to at least two different species of Brassica, horticulturalists have defined and named a number of varieties. For example, a resource provided by Cornell University and the United States Department of Agriculture lists sixteen varieties including "Early Mizuna", "Kyona Mizuna", "Komatsuna Mizuna", "Vitamin Green Mizuna", "Kyoto Mizuna", "Happy Rich Mizuna", "Summer Fest Mizuna", "Tokyo Early Mizuna", "Mibuna Mizuna", "Red Komatsuna Mizuna", "Waido Mizuna" and "Purple Mizuna".
One fast-growing variety called "Organic Early Mizuna Mustard Salad Greens" by its Indiana-based seller reaches maturity in 48 days at 12 - 24†tall
Mizuna is a mild mustard green. Also known as Spider Mustard, its scientific name is Brassica rapa, which indicates it is related to broccoli and cabbage, with similar nutritional value. And like other brassica vegetables, it contains glucosinolates.
...contains vitamin C, folic acid, and antioxidants. And like other brassica vegetables, it contains glucosinolates, which may inhibit the development of certain cancers. Glucosinolates are the compounds that give brassicas, like Brussels sprouts and cabbage, their bitter flavor. Cultivated varieties of Brassica rapa include:
• Chinese cabbage: Bok choi (chinensis group) and Napa cabbage (pekinensis group)
• Mizuna (nipposinica group)
• Aburana (nippo-oleifera group)
• Flowering cabbage (parachinensis group)
• Turnip (rapa group)
• Turnip rape (Brassica rapa subsp. oleifera) [2]
• Rapini (ruvo group)
• Tatsoi
• Komatsuna
Mustard Greens: 104mg - 58 mg ratio of 1.8:1
Nutritional info on mustard though this is also boiledhttp://www.whfoods.com/genpage.php?tname=nutrientprofile&dbid=36
See other Cruciferous vegitables
http://en.wikipedia.org/wiki/Cruciferous_vegetables
Chicory Family:
Endive:
Family: Asteraceae
Genus: Cichorium
Species: C endivia
Binominal Name: Cichorium endivia
Frisee and Radicchio
Family: Asteraceae
Tribe: Cichorieae
Genus: Cichorium
Species: C. intybus
Binominal Name: Cichorium intybus
Endive belongs to the chicory genus, which includes several similar bitter leafed vegetables. Species include endive (Cichorium endivia), Cichorium pumilum and common chicory (Cichorium intybus). Common chicory includes chicory types such as radicchio, puntarelle and Belgian endive.
Endive is rich in many vitamins and minerals, especially in folate and vitamins A and K, and is high in fiber.
There are two main varieties of cultivated endive:
Frisée
• Curly endive, or frisée (var crispum). This type has narrow, green, curly outer leaves. Sometimes called chicory in the United States and is called chicorée frisée in French. Further confusion results from the fact that frisée also refers to a technique in which greens are lightly wilted with oil.
• Escarole, or broad-leaved endive (var latifolia) has broad, pale green leaves and is less bitter than the other varieties. Varieties or names include broad-leaved endive, Bavarian endive, Batavian endive, grumolo, scarola and scarole.
Common chicory (Cichorium intybus) is a bushy perennial herb with blue, lavender, or occasionally white flowers. It grows as a wild plant on roadsides in its native Europe, and in North America and Australia, where it has become naturalized. Common chicory is also known as blue sailors, succory, and coffeeweed. It is also called cornflower, although that name is more properly applied to Centaurea cyanus. The cultivated forms are grown for their leaves (var. foliosum), or for the roots (var. sativum), which are baked, ground, and used as a coffee substitute and additive. Common names for varieties of var. foliosum include endive, radicchio, Belgian endive, French endive, red endive, sugarloaf or witloof.
Chicory is also the common name in the US (and in France) for curly endive (Cichorium endivia). There is considerable confusion between Cichorium endivia and Cichorium intybus.
Leaf chicory
Chicory may be grown for its leaves, eaten raw as a salad. It is generally divided into three types of which there are many varieties
• Radicchio usually has variegated red or red and green leaves. Some only refer to the white-veined red leaved type as radicchio. Also known as red endive and red chicory. It has a bitter and spicy taste, which mellows when it is grilled or roasted. It can also be used to add color and zest to salads.
• Sugarloaf looks rather like cos lettuce, with tightly packed leaves.
• Belgian endive is also known as French endive, witlof in the Netherlands, witlo(o)f in the USA, chicory in the UK, as witlof in Australia, endive in France, and chicon in parts of Northern France and in Wallonia. It has a small head of cream-coloured, bitter leaves. It is grown completely underground or indoors in the absence of sunlight in order to prevent the leaves from turning green and opening up (etiolation). Not suggested for tortoise diet.
Although leaf chicory is often called "endive", true endive (Cichorium endivia) is a different species in the genus.
The bitter substances are primarily the two sesquiterpene lactones Lactucin and Lactucopicrin. Other ingredients are Aesculetin, Aesculin, Cichoriin, Umbelliferone, Scopoletin and 6.7-Dihydrocoumarin and further sesquiterpene lactones and their glycosides.
http://en.wikipedia.org/wiki/Glycoside
Calcium & Phosphorous Content of Common Vegetables & Fruits http://www.swanimalhospital.net/html/veggie_info.html
Some information from:
http://plants.usda.gov/java/profile?symbol=LACTU
http://www.reimerseeds.com/lollo-rosa-lettuce.aspx
http://urbanext.illinois.edu/veggies/lettuce1.html
http://en.wikipedia.org
Most plants carry what we look at as toxins of some sort. What we need to remember is the amount that is in the plant and the amount we feed to our animals. Some people would prefer to steer clear of Oxalic acid, others glucosinolates, or glycosides, or high protiens, or tannins, etc. I do not think we have yet gotten down to a science how to feed our tortoises regarding the amount of which toxin is infact harmful to them. So we feed a variety of greens to minimize the risk of concentrating one toxin or another. Each keeper needs to decide what and how they are going to provide a diet for their particular species. Because not only are their toxins in all plants but the amount can vary depending on how it is grown, time of harvesting, etc.
The information given here is stricly to inform.