The Greek word 'zizania' appears in Jesus’ 'Parable of The Wheat and the Tares', in Matthew 13:24–30. This word is translated as ‘tares’ in the KJV and as ‘weeds’ in the NIV. 

Darnel1

The Darnel (Lolium temulentum). PICTURE H Zell (licensed under CC BY-SA 3.0)

Jesus told them another parable: “The Kingdom of Heaven is like a man who sowed good seed in his field. But while everyone was sleeping, his enemy came and sowed zizania [weeds) among the wheat, and went away. When the wheat sprouted and formed heads, then the weeds also appeared." 
     The owner’s servants came to him and said, “Sir, didn’t you sow good seed in your field? Where then did the zizania [weeds] come from?”
     “An enemy did this,’’ he replied.
     The servants asked him, “Do you want us to go and pull them up?”
     “No,” he answered, “because while you are pulling the zizania [weeds], you may uproot the wheat with them. Let both grow together until the harvest. At that time I will tell the harvesters: First collect the zizania [weeds] and tie them in bundles to be burned; then gather the wheat and bring it into my barn."  

It is thought that the zizania is the darnel (Lolium temulentum). Darnel usually grows in the same regions as wheat and is considered a weed.

Darnel is found around the world. It is an annual plant and its stem can grow up to a metre in height. It has purple grain.

The similarity between wheat and darnel is so great that in some regions darnel is referred to as ‘false wheat'. It is only when the ear appears that the difference becomes obvious. The wheat ears are heavier and will droop, and the wheat will appear brown when ripe, whereas the darnel is purple/black. This is why in the parable the uprooting of the darnel must happen closer to harvest time, when the differences are more noticeable.

In the Parable of the Wheat and Tares, darnel is to be pulled up before the harvest. This is because the seed is highly poisonous and must not be mixed with the grain.

This is an edited excerpt from Alvin Johnson's iBook 'Biblical Flora', 2017. The book is available for free download on iTunes. A teacher's edition is also available for purchase.