In any crop, it’s just as important to know what is going on under the ground as it is to know what’s going on above ground. In a pulse crop, it is particularly important because pulses fix their own nitrogen and you have to actually see the roots to know what is going on.
In this episode of the Pulse School, field editor Dale Leftwich talks to Wendy Schatz Leeds, lead agronomist with Sharpe’s Crop Services, about nodulation.
What is the right time to scout a pea field for nodulation and what are the things to look for?
The field Schatz Leeds is scouting (above) is a little more mature than when you would usually start assessing your inoculant and nodulation, but continued monitoring is helpful and informative.
According to Schatz Leeds. “Nodules set just when it starts to actively grow and elongate, but it’s still nice to see if they are fixing nitrogen so I always dig up a plant, look for good nodulation on the root system and slice open a nodule and look for the blood red colour to see if it’s fixing.”
The first thing to check is for the presences of nodules and that they are evenly distributed throughout the root system. Schatz Leeds says “I want nodules both on the crown and along all the secondary roots, which is what we see, and we also look for healthy nodulation.”
The second thing to check is to make sure the nodules aren’t freeloaders. That is, taking energy from the plant and making nodules, but not fixing nitrogen for the plant.
When broken open the nodules should be blood red inside. Schatz Leeds says “Red colour is important. It shows it is fixing nitrogen.”
What could it mean if you don’t have decent nodulation? It’s time to evaluate your nodulation set up, routine, and timing. (Check out these tips on maximizing nodulation)