In The Field

A visit to Nomura’s exclusive Rice Research Station.

Nomura & Company is virtually unique among California’s rice producers in its commitment to research and development. Our breeding program at Rice Researchers Inc. comprises upwards of 1000 test plots, and we have 35 years of continuous botanical data as our research legacy. We emphasize table quality (aroma, taste, texture, tenderness, and sheen) over agricultural yield, which sets us apart from other programs, both public and private.

The Station

Rice Researchers Inc. – the Station – is about 30 minutes north-east of the town of Willows, California and less than 5 minutes west of the Sacramento River. The Station complex consists of a main office, a temperature-controlled greenhouse, and several silos and outbuildings.

Our goals at the Station are simple

  1. To maintain the integrity of proprietary seed stocks
  2. To develop rice varieties that set new standards for table quality
  3. To meet the needs of our community of growers

To appreciate why Nomura’s breeding program is special, you have to know a bit about California’s rice industry, and a few things about farming rice.

Almost all the rice grown in California comes from seed purchased from the state. Because high grain yield is economically attractive to rice growers, government scientists emphasize grain yield above other characteristics.

Yield is determined by many factors, including the number of stalks on each plant and the number of seeds in a panicle; resistance to insects and disease; time to mature; tolerance to cold; and ease of harvesting. The last factor — ease of harvesting — is largely determined by the height of the plant. Tall varieties of rice are more likely to be pushed over by high winds or heavy rain, a phenomenon known as lodging. Once rice has lodged it takes longer to harvest and inevitably some of the crop is lost.

For Nomura, taste always comes before yield.

Kokuho Rose®, renowned for its superior table quality, is an example of our commitment to premium rice. Kokuho Rose® is not easy to farm and it’s not high yield. The original variety, which we still grow extensively, takes a long time to mature and is prone to lodging because it’s unusually tall. Even the shorter versions we’ve developed through decades of breeding require careful tending. It’s worth it though, because Kokuho Rose® consistently outscores the competition in taste tests.

The Japanese have developed a formal scoring system to grade the quality of sushi rice. The scale runs from 0 – 100, with 100 being the best possible score.

Most Calrose cooks at around 70.

Kokuho Rose® cooks at 84, making it a true premium rice.


All of Nomura’s rice is GMO-free, because our research program is based entirely on classical plant-breeding techniques. It’s tried-and-true science but very labor-intensive, involving careful selection and the use of manual pollination to cross plants that have desirable genetic characteristics.

The journey to a new variety begins with a handful of seed taken from a single panicle and sown in a 5-foot row. If those plants look promising at the end of a growing season, they in turn provide the seed for a larger “block” of plants. With each successive generation, the blocks become larger.

Once we confirm that a variety performs consistently in our test plots at the Station (with taste being the ultimate measure), we move to replicated trials with a small number of growers throughout the Sacramento Valley. This crucial stage indicates the effects of different micro-climates and soil characteristics on the rice, and separates out those varieties that aren’t well adapted to a range of conditions.

In total it takes at least 12 generations (each generation = 1 growing season) to fully establish that a new variety is stable and viable. Along the way, literally millions of individual plants have been bred, grown, examined, and discarded to find the one plant that has a mix of characteristics that make it worth cultivating – and worth eating!

It’s all about the taste.

Much of our work has focused on maintaining and improving the original Kokuho Rose® tall variety, which continues to produce some of the best medium-grain rice in the world.

We’ve also developed several shorter-statured varieties of Kokuho Rose® that are easier to harvest. Having multiple varieties of Kokuho® is a key part of our blending method, which guarantees that every bag, no matter what time of year, cooks up to the Nomura standard of high quality.


One of Nomura’s long-term goals is to produce a short-grain rice that surpasses Japanese short-grains, the epitome of quality for sushi lovers around the world. Some of our most promising and exciting work is now coming of age at the Station. After years of research we’re on the threshold of having a California-grown short-grain rice that can take a place of honor alongside its Japanese peers.