It does say that. And often that is overlooked by members in Christ's flock.
Tares in the parables of Christ were in actual life what is called darnel seed, also called ryegrass. It looks like wheat but it does not produce the same. In Jesus parable of the sower in Matthew 13, he speaks of one who came into the field and sewed the dreaded darnel grass that does not bear wheat for the labor as would the actual wheat. It is false though it appears like wheat.
The one who sneaks into the field to sew the ryegrass is comparison to the world and the message therein is the enemy of the farmer. That which would have his crop yield him nothing for the bounty of a full crop of wheat. But rather would have instead that the farmer lose his ability to sustain himself at the harvest with the blindness in the winowing of ryegrass.
That sower of the darnel seed is the enemy of the church. Hoping to seed fracture into the congregation.
I witnessed this in my former church. I knew then it was changing and the sewing that was going on was to corrupt the flock dedicated to truth and light. Because the human tare assuming the guise of bountiful wheat will then cause in its germination in the field for as long as it is allowed to in human terms call the wheat's identity into question. By its flourishing the ryegrass over populating the wheat then makes the wheat appear to be the interloper. The weed.
I should add, this parable is that which embodies the wisdom in Matthew 7. "You will recognize them by their fruits. Are grapes gathered from thornbushes, or figs from thistles?"
That which seeks to sew discord into the peace of Christ are examples of this. They're found to flourish on the Internet due to the anonymity factor. However, just because we read each other rather than speak face to face does not mean we are not able to discern that which is the sower of the weed. The fruits are then discerned word for word, seed by seed, that is hoped to take root and distance the members of the church from one another. Making an unhealthy slight crop that would otherwise be lush furrows of wheat.