I thought you tended to be skeptical of things that cannot be proven? Yet there you are making a very unprovable statement (bolded). There could be lots of reasons to not eat the fruit of certain trees and you just don't know what they are. The passage did not spell out the reason but it did generally say that it's purpose was to increase the harvest in the fifth year.
Did you even do any research before you declared that there was "no reason"? I just did some and I found this:
"23-25. ye shall count the fruit thereof as uncircumcised; three years . it shall not be eaten of-"The wisdom of this law is very striking. Every gardener will teach us not to let fruit trees bear in their earliest years, but to pluck off the blossoms: and for this reason, that they will thus thrive the better, and bear more abundantly afterwards. The very expression, 'to regard them as uncircumcised,' suggests the propriety of pinching them off; I do not say cutting them off, because it is generally the hand, and not a knife, that is employed in this operation" [Michaelis]."
http://bible.cc/leviticus/19-23.htm
Now I will check with a gardening site to see if it is true:
I found this:
"Fruit tree likely produce flowers by the second year spring. The flowers would develop into fruit if you allow them (too early). Pinch off these flowers allow the tree another full year to develop a strong root system. They will grow to be stronger and healthier."
http://74.125.95.132/search?q=cache...ree&cd=5&hl=en&ct=clnk&gl=us&client=firefox-a
Is this another example where you thought the bible was ludicrous yet it turned out to be right on? Will you continue to think that your own understanding is better in every single instance one by one until there are none left to dispute? If so do you approach every branch of thought the same way, or just the bible? What would happen if in many instances you gave the bible the benefit of the doubt and reserved your skepticism for a select few? At least that way you would have enough time in your life to thoroughly examine them all.
I do have to admit I read the passage incorrectly and commented on it here, thus throwing you off. I thought that it referred to trees they found already growing there and in reading the passage again it clearly says they are planting the trees.
I even found further reason to always read multiple versions of a passage. It tends to show us the range of possible meanings for the words translated. Here is one version of that passage:
Leviticus 19:23
"When you shall be come into the land, and shall have planted in it fruit trees, you shall take away the firstfruits of them: the fruit that comes forth shall be unclean to you, neither shall you eat of them."
Contrast and compare that to this:
Leviticus 19:23
"And when you have come into the land, and have put in all sorts of fruit-trees, their fruit will be as if they had not had circumcision, and for three years their fruit may not be used for food."
Both translators accurately captured the intent of the passage. But the range of possible meanings for the words in the middle leave us modern readers not quite sure about what it means to think of the fruit as either not having circumcision or being taken away. I have no doubt that a person hearing the words at the time they were spoken or reading the original in the original language would have no such problem. You and I need to do some work - not always but sometimes.