surah al-Baqarah 2:223: " Your wives are as a tilth unto you; so approach your tilth when or how ye will; but do some good act for your souls beforehand; and fear Allah. And know that ye are to meet Him (in the Hereafter), and give (these) good tidings to those who believe."
I point out, again, like a broken record, that the author only uses the first part of the verse, ending with 'approach your tilth when or how ye will'. I admit that this one gave me problems too, especially before I read the entire verse. I, on my own, decided that this was an example of the mentality of the age. Wives, in all cultures and religions of the time were essentially property. Valuable only for the prestige they might bring, if they were exceptionally beautiful or had some other quality, or for the number of sons they bore. Sons, not daughters. Because girls were burdens. It's not an attitude limited to one culture or another.
The tafsir I've read, however, has this explanation, basically. This verse follows on the verse that prohibits sex between a married couple while the wife is menstruating. Anal sex, by the way, is also considered forbidden. Just in case you were wondering. Anyway. The two verses, 222 & 223 are connected. First the Qur'an says that men are forbidden from having/asking for sex from their wives while they are menstruating (which, depending on the woman is either a good thing or just annoying), then it explains that once she has cleansed herself (I think the word is ghusl) the man is permitted to come to her in any way that Allah has allowed. Which is where the 'tilth' or 'field' comes into play. The field is a fertile image, reminding/hinting at the vagina and the womb. So the verse, along with the preceding is informing the men that they should only have sex with their wives in the proper time and orifice. Which is what a *lot* of Christians will tell you as well. We may not like the imagery, but it is what it is. The Qur'an was written in an agricultural society 1,400 years ago. What they would find understandable and meaningful is not necessarily what we do.
The next surah she cites as making the wife a possession is surah al-'Imran 3:14 (but not all of it, just the part she wants...): " Fair in the eyes of men is the love of things they covet: Women and sons; Heaped-up hoards of gold and silver; horses branded (for blood and excellence); and (wealth of) cattle and well-tilled land. Such are the possessions of this world's life; but in nearness to Allah is the best of the goals (To return to)."
This is one of those cases where 'I do not think that means what you say it means' comes into play. Yes, women are listed as amongst the things that men covet. Is that really a surprise to anyone? Is it a statement of approval? I think not. Merely one of fact. Men want women, sons, money, land, cool toys, fast cars and lots of all of them. "Such are the possessions of this world's life" - these are the things we can have in this world. But they don't last into the next, and that's reflected in the next section "in nearness to Allah is the best of the goals (to return to)". Don't Christians say that closeness to Christ, to God, is the true goal of our lives? It seems to me that this is saying the same thing. There are the riches of the world and the riches of eternity.